diff --git a/dev/js/spec/hintSpec.js b/dev/js/spec/hintSpec.js
index 20935e1..ac50f0f 100644
--- a/dev/js/spec/hintSpec.js
+++ b/dev/js/spec/hintSpec.js
@@ -74,13 +74,13 @@
 
       expect(input.selectionStart).toEqual(5);
       expect(inputField.element().selectionStart).toEqual(5);
-      expect(inputField.split()[0]).toEqual("abcde");
-      expect(inputField.split()[1]).toEqual("fghijklmno");
+      expect(inputField._split()[0]).toEqual("abcde");
+      expect(inputField._split()[1]).toEqual("fghijklmno");
 
       inputField.insert("xyz");
       expect(inputField.value()).toEqual('abcdexyzfghijklmno');
-      expect(inputField.split()[0]).toEqual("abcdexyz");
-      expect(inputField.split()[1]).toEqual("fghijklmno");
+      expect(inputField._split()[0]).toEqual("abcdexyz");
+      expect(inputField._split()[1]).toEqual("fghijklmno");
     });
 
     it('should be correctly positioned', function () {
@@ -98,7 +98,7 @@
       var inputField = inputClass.create(input);
       expect(inputField.value()).toEqual("abcdefghijklmno");
       expect(inputField.element().selectionStart).toEqual(5);
-      expect(inputField.split()[0]).toEqual("abcde");
+      expect(inputField._split()[0]).toEqual("abcde");
       expect(inputField.context()).toEqual("abcde");
     });
 
@@ -385,7 +385,6 @@
     it('should be initializable', function () {
 
       var menu = menuClass.create(null, "cnx/", list);
-      expect(menu.context()).toEqual('cnx/');
       expect(menu.element().nodeName).toEqual('UL');
       expect(menu.element().style.opacity).toEqual("0");
 
diff --git a/dev/js/spec/menuSpec.js b/dev/js/spec/menuSpec.js
index 7436e4d..999ec2b 100644
--- a/dev/js/spec/menuSpec.js
+++ b/dev/js/spec/menuSpec.js
@@ -1,7 +1,8 @@
 define(['menu'], function () {
 
   var menuItemClass = require('menu/item');
-  var menuClass = require('menu');
+  var prefixClass   = require('menu/prefix');
+  var menuClass     = require('menu');
 
   // The OwnMenu item
   KorAP.OwnMenuItem = {
@@ -800,13 +801,13 @@
       expect(menu.shownItem(0).name()).toEqual("Autor");
       expect(menu.element().childNodes[1].innerHTML).toEqual("<strong><mark>Au</mark>tor</strong>");
 
-      menu._prefix.backspace();
+      menu._prefix.chop();
       expect(menu.show()).toBe(true);
       expect(menu.prefix()).toEqual("a");
       expect(menu.shownItem(0).name()).toEqual("Autor");
       expect(menu.element().childNodes[1].innerHTML).toEqual("<strong><mark>A</mark>utor</strong>");
 
-      menu._prefix.backspace();
+      menu._prefix.chop();
       expect(menu.show()).toBe(true);
       expect(menu.prefix()).toEqual("");
       expect(menu.shownItem(0).name()).toEqual("Titel");
@@ -821,7 +822,7 @@
       expect(menu.shownItem(3)).toBe(undefined);
 
       // Forward
-      menu._prefix.backspace();
+      menu._prefix.chop();
       expect(menu.show()).toBe(true);
       expect(menu.prefix()).toEqual("");
       expect(menu.shownItem(0).name()).toEqual("Titel");
@@ -1054,7 +1055,78 @@
     xit('should be page downable');
     xit('should be page upable');
 
-    xit('should scroll to a chosen value')
-    xit('should highlight a chosen value')
+    xit('should scroll to a chosen value');
+    xit('should highlight a chosen value');
+  });
+
+  describe('KorAP.Prefix', function () {
+    it('should be initializable', function () {
+      var p = prefixClass.create();
+      expect(p.element().classList.contains('pref')).toBeTruthy();
+      expect(p.isSet()).not.toBeTruthy();
+
+/*
+      expect(mi.lcField()).toEqual(' baum');
+*/
+      
+    });
+
+    it('should be modifiable', function () {
+      var p = prefixClass.create();
+      expect(p.value()).toEqual('');
+      expect(p.element().firstChild).toBeNull();
+
+      // Set string
+      expect(p.value('Test')).toEqual('Test');
+      expect(p.value()).toEqual('Test');
+      expect(p.element().firstChild.nodeValue).toEqual('Test');
+
+      // Add string
+      expect(p.add('ified')).toEqual('Testified');
+      expect(p.value()).toEqual('Testified');
+      expect(p.element().firstChild.nodeValue).toEqual('Testified');
+
+      // Clear string
+      p.clear();
+      expect(p.value()).toEqual('');
+      expect(p.element().firstChild).toBeNull();
+
+      // Set string
+      expect(p.value('Test')).toEqual('Test');
+      expect(p.value()).toEqual('Test');
+      expect(p.element().firstChild.nodeValue).toEqual('Test');
+
+      expect(p.chop()).toEqual('Tes');
+      expect(p.value()).toEqual('Tes');
+      expect(p.element().firstChild.nodeValue).toEqual('Tes');
+
+      expect(p.chop()).toEqual('Te');
+      expect(p.value()).toEqual('Te');
+      expect(p.element().firstChild.nodeValue).toEqual('Te');
+
+      expect(p.chop()).toEqual('T');
+      expect(p.value()).toEqual('T');
+      expect(p.element().firstChild.nodeValue).toEqual('T');
+
+      expect(p.chop()).toEqual('');
+      expect(p.value()).toEqual('');
+      expect(p.element().firstChild).toBeNull();
+    });
+
+    it('should be activatable', function () {
+      var p = prefixClass.create();
+      expect(p.value()).toEqual('');
+      expect(p.element().firstChild).toBeNull();
+
+      expect(p.value('Test')).toEqual('Test');
+      expect(p.element().firstChild.nodeValue).toEqual('Test');
+
+      expect(p.active()).not.toBeTruthy();
+      expect(p.element().classList.contains('active')).not.toBeTruthy();
+
+      p.active(true);
+      expect(p.active()).toBeTruthy();
+      expect(p.element().classList.contains('active')).toBeTruthy();
+    });
   });
 });
diff --git a/dev/js/src/app/de.js b/dev/js/src/app/de.js
new file mode 100644
index 0000000..fc576f2
--- /dev/null
+++ b/dev/js/src/app/de.js
@@ -0,0 +1,26 @@
+define(['init'], function () {
+  var loc = KorAP.Locale;
+  loc.OR = 'oder';
+  loc.AND = 'und';
+  // EMPTY, DELETE
+
+  // Virtual collection:
+  loc.VC_subTitle = 'Untertitel';
+  loc.VC_title = 'Titel';
+  loc.VC_pubDate = 'Veröffentlichungsdatum';
+  loc.VC_pubPlace = 'Veröffentlichungsort';
+
+  // Date picker:
+  loc.WDAY = ['Mo', 'Di', 'Mi', 'Do', 'Fr', 'Sa', 'So'];
+  loc.MONTH = [
+    'Januar', 'Februar', 'März', 'April',
+    'Mai', 'Juni', 'Juli', 'August',
+    'September', 'Oktober', 'November',
+    'Dezember'
+  ];
+
+  // Match view
+  loc.ADDTREE  = 'Baumansicht hinzufügen';
+  loc.SHOWINFO = 'Informationen';
+  loc.CLOSE    = 'Schließen';
+});
diff --git a/dev/js/src/app/en.js b/dev/js/src/app/en.js
new file mode 100644
index 0000000..c7a4e5c
--- /dev/null
+++ b/dev/js/src/app/en.js
@@ -0,0 +1 @@
+require(['init']);
diff --git a/dev/js/src/datepicker.js b/dev/js/src/datepicker.js
index 90b0572..6d3086d 100644
--- a/dev/js/src/datepicker.js
+++ b/dev/js/src/datepicker.js
@@ -1,16 +1,19 @@
 /**
- * Date picker for the
+ * Simple Date picker for the
  * Virtual Collection builder.
+ *
+ * @author Nils Diewald
  */
 define(['util'], function () {
   "use strict";
 
+  /*
+   * Localizations
+   */
   var loc = KorAP.Locale;
-
   loc.WDAY = loc.WDAY || [
     'Mo', 'Tu', 'We', 'Th', 'Fr', 'Sa', 'Su'
   ];
-
   loc.MONTH = loc.MONTH || [
     'January', 'February', 'March', 'April',
     'May', 'June', 'July', 'August',
@@ -20,27 +23,24 @@
 
   var d = document;
 
+  // The datepicker class
   return {
+
+    /**
+     * Create a new datepicker view.
+     */
     create : function () {
       return Object.create(this)._init();
     },
 
+    // Init datepicker
     _init : function () {
       return this;
     },
 
-    set : function (year, month, day) {
-      this.select(year, month, day);
-      if (this._click !== undefined)
-	this._click(this._selected);
-      else 
-	console.dir(this._selected);
-    },
-
-    onclick : function (cb) {
-      this._click = cb;
-    },
-
+    /**
+     * Get or select a specific date.
+     */
     select : function (year, month, day) {
       if (arguments.length >= 1) {
 	this._selected = {'year' : year};
@@ -54,21 +54,73 @@
       return this._selected;
     },
 
+
+    /**
+     * Select a specific date and
+     * init the accompanied action.
+     */
+    set : function (year, month, day) {
+      this.select(year, month, day);
+      if (this._click !== undefined)
+	this._click(this._selected);
+      else 
+	console.dir(this._selected);
+    },
+
+
+    /**
+     * Set the action for clicking as a callback.
+     * The callback will retrieve a an object with
+     * an optional year attribute,
+     * an optional month attribute,
+     * and an optional day attribute
+     */
+    onclick : function (cb) {
+      this._click = cb;
+    },
+
+    /**
+     * Show the datepicker.
+     * Will either show the selected year/month
+     * or the current date.
+     * Will return the element for appending to the dom.
+     */
     show : function (year, month) {
-      this._element = d.createElement('div');
-      this._element.classList.add('datepicker');
-      this._showYear = year ? year : (this._selected['year'] ? this._selected['year'] : 2012);
-      this._showMonth = month ? month : (this._selected['month'] ? this._selected['month'] : 2);
+      var e = this._element = d.createElement('div');
+      e.setAttribute('tabindex', 0);
+      e.style.outline = 0;
+      e.classList.add('datepicker');
+
+      var today = new Date();
+
+      // Show year
+      this._showYear = year ? year :
+	(this._selected['year'] ? this._selected['year'] :
+	 today.getYear());
+
+      // Show month
+      this._showMonth = month ? month :
+	(this._selected['month'] ? this._selected['month'] :
+	 (today.getMonth() + 1));
+
+      // Append all helpers
       this._element.appendChild(this._monthHelper());
       this._element.appendChild(this._yearHelper());
       this._element.appendChild(this._dayHelper());
       return this._element;
     },
 
+    /**
+     * Get the HTML element associated with the datepicker.
+     */
     element : function () {
       return this._element;
     },
 
+
+    /**
+     * Increment the year.
+     */
     incrYear : function () {
       this._showYear++;
       this._updateYear();
@@ -77,6 +129,9 @@
       return;
     },
 
+    /**
+     * Decrement the year.
+     */
     decrYear : function () {
       this._showYear--;
       this._updateYear();
@@ -85,6 +140,9 @@
       return;
     },
 
+    /**
+     * Increment the month.
+     */
     incrMonth : function () {
       this._showMonth++;
       if (this._showMonth > 12) {
@@ -97,6 +155,9 @@
       };
     },
 
+    /**
+     * Decrement the month.
+     */
     decrMonth : function () {
       this._showMonth--;
       if (this._showMonth < 1) {
@@ -109,6 +170,8 @@
       };
     },
 
+
+    // Create the year helper element.
     _yearHelper : function () {
       var year = d.createElement('div');
       year.classList.add('year');
@@ -123,6 +186,7 @@
       this._yElement.onclick = function () {
 	this.set(this._showYear);
       }.bind(this);
+      this._selectYear();
 
       // Increment year
       year.appendChild(d.createElement('span'))
@@ -131,10 +195,23 @@
       return year;
     },
 
+    // Update the year helper view.
     _updateYear : function () {
       this._yElement.firstChild.data = this._showYear;
+      this._selectYear();
     },
 
+
+    // Check if the viewed year is current
+    _selectYear : function () {
+      if (this._showYear === this.select()['year'])
+	this._yElement.classList.add('selected');
+      else
+	this._yElement.classList.remove('selected');
+    },
+
+
+    // Create the month helper element.
     _monthHelper : function () {
       var month = d.createElement('div');
       month.classList.add('month');
@@ -150,6 +227,8 @@
       this._mElement.onclick = function () {
 	this.set(this._showYear, this._showMonth);
       }.bind(this);
+
+      this._selectMonth();
       
       // Increment month
       month.appendChild(d.createElement('span'))
@@ -158,13 +237,28 @@
       return month;
     },
 
+    // Update the month helper view.
     _updateMonth : function () {
       this._mElement.firstChild.data = loc.MONTH[this._showMonth-1];
+      this._selectMonth();
     },
 
+
+    // Check if the viewed month is current
+    _selectMonth : function () {
+      if (this._showYear === this.select()['year'] &&
+	  this._showMonth === this.select()['month'])
+	this._mElement.classList.add('selected');
+      else
+	this._mElement.classList.remove('selected');
+    },
+
+
+    // Create the day (calendar) helper element.
     _dayHelper : function () {
       var table = d.createElement('table');
 
+      // Localized day view
       var tr = table.appendChild(d.createElement('thead'))
 	.appendChild(d.createElement('tr'));
       for (var i = 0; i < 7; i++) {
@@ -179,10 +273,29 @@
     },
 
     _dayBody : function () {
-      var showDate = new Date(this._showYear, this._showMonth - 1, 1, 0, 0, 0, 0);
-      var date     = new Date(this._showYear, this._showMonth - 1, 1, 0, 0, 0, 0);
-      var today    = new Date();
+      var showDate = new Date(
+	this._showYear,
+	this._showMonth - 1,
+	1,
+	0,
+	0,
+	0,
+	0
+      );
+      var date = new Date(
+	this._showYear,
+	this._showMonth - 1,
+	1,
+	0,
+	0,
+	0,
+	0
+      );
+      var today = new Date();
       var that = this;
+
+      // What happens, in case someone clicks
+      // on a date
       var click = function () {
 	that.set(
 	  that._showYear,
@@ -245,6 +358,7 @@
       return tb;
     },
 
+    // Update the calendar view
     _updateDay : function () {
       var newBody = this._dayBody();
       this._dBElement.parentNode.replaceChild(
diff --git a/dev/js/src/hint/contextanalyzer.js b/dev/js/src/hint/contextanalyzer.js
index bdbf885..fc01662 100644
--- a/dev/js/src/hint/contextanalyzer.js
+++ b/dev/js/src/hint/contextanalyzer.js
@@ -2,9 +2,15 @@
  * Regex object for checking the context of the hint
  */
 define({
+
+  /**
+   * Create analyzer based on regular expression.
+   */
   create : function (regex) {
     return Object.create(this)._init(regex);
   },
+
+  // Initialize analyzer
   _init : function (regex) {
     try {
       this._regex = new RegExp(regex);
@@ -15,6 +21,11 @@
     };
     return this;
   },
+
+  /**
+   * Check a context based on the analyzer
+   * and return a valid context string.
+   */
   test : function (text) {
     if (!this._regex.exec(text))
       return;
diff --git a/dev/js/src/hint/input.js b/dev/js/src/hint/input.js
index b1c6632..c12d26a 100644
--- a/dev/js/src/hint/input.js
+++ b/dev/js/src/hint/input.js
@@ -1,9 +1,14 @@
 // Input field for queries
 define({
+
+  /**
+   * Create a new input field.
+   */
   create : function (element) {
     return Object.create(this)._init(element);
   },
-    
+  
+  // Initialize new input field
   _init : function (element) {
     this._element = element;
 
@@ -29,34 +34,62 @@
     return this;
   },
 
-  rightPos : function () {
+  // Get the right position
+  _rightPos : function () {
     var box = this._mirror.firstChild.getBoundingClientRect();
     return box.right - box.left;
   },
 
+  /**
+   * Get the mirrored input field.
+   */
   mirror : function () {
     return this._mirror;
   },
 
+
+  /**
+   * Get the container element.
+   * This contains the mirror and
+   * the hint helper.
+   */
   container : function () {
     return this._container;
   },
 
+
+  /**
+   * Get the input element the
+   * hint helper is attached to.
+   */
   element : function () {
     return this._element;
   },
 
+  /**
+   * Get the value of the input field
+   * the hint helper is attached to.
+   */
   value : function () {
     return this._element.value;
   },
 
+
+  /**
+   * Update the mirror content.
+   */
   update : function () {
-    this._mirror.firstChild.textContent = this.split()[0];
-    this._container.style.left = this.rightPos() + 'px';
+    this._mirror.firstChild.textContent = this._split()[0];
+    this._container.style.left = this._rightPos() + 'px';
   },
 
+  /**
+   * Insert text into the mirror.
+   * This is a prefix of the input field's
+   * value.
+   */
   insert : function (text) {
-    var splittedText = this.split();
+    var splittedText = this._split();
     var s = this._element;
     s.value = splittedText[0] + text + splittedText[1];
     s.selectionStart = (splittedText[0] + text).length;
@@ -64,18 +97,11 @@
     this._mirror.firstChild.textContent = splittedText[0] + text;
   },
   
-  // Return two substrings, splitted at current cursor position
-  split : function () {
-    var s = this._element;
-    var value = s.value;
-    var start = s.selectionStart;
-    return new Array(
-      value.substring(0, start),
-      value.substring(start, value.length)
-    );
-  },
 
-  // Position the input mirror directly below the input box
+  /**
+   * Reposition the input mirror directly
+   * below the input box.
+   */
   reposition : function () {
     var inputClientRect = this._element.getBoundingClientRect();
     var inputStyle = window.getComputedStyle(this._element, null);
@@ -97,7 +123,27 @@
     mirrorStyle.fontSize        = inputStyle.getPropertyValue("font-size");
     mirrorStyle.fontFamily      = inputStyle.getPropertyValue("font-family");
   },
+
+  /**
+   * Get the context, which is the input
+   * field's value bounded to the
+   * cursor position.
+   */
   context : function () {
-    return this.split()[0];
+    return this._split()[0];
+  },
+
+  /*
+   * Return two substrings,
+   * splitted at the current cursor position.
+   */
+  _split : function () {
+    var s = this._element;
+    var value = s.value;
+    var start = s.selectionStart;
+    return new Array(
+      value.substring(0, start),
+      value.substring(start, value.length)
+    );
   }
 });
diff --git a/dev/js/src/hint/item.js b/dev/js/src/hint/item.js
index 4b879f8..b9a1bc8 100644
--- a/dev/js/src/hint/item.js
+++ b/dev/js/src/hint/item.js
@@ -3,12 +3,17 @@
  */
 define(['menu/item'], function (itemClass) {
   return {
+
+    /**
+     * Create new menu item object.
+     */
     create : function (params) {
       return Object.create(itemClass)
 	.upgradeTo(this)
 	._init(params);
     },
 
+    // Initialize menu item object
     _init : function (params) {
       if (params[0] === undefined ||
 	  params[1] === undefined)
@@ -26,13 +31,20 @@
       return this;
     },
 
+    /**
+     * Get or set the content of the item.
+     */
     content : function (content) {
       if (arguments.length === 1) {
 	this._content = content;
       };
       return this._content;
     },
-    
+
+    /**
+     * Override the click action
+     * of the menu item.
+     */
     onclick : function (e) {
       var m = this.menu();
       var h = m.hint();
@@ -50,15 +62,32 @@
       h.show(true);
     },
 
+    /**
+     * The name of the menu entry.
+     */
     name : function () {
       return this._name;
     },
+
+    /**
+     * The action (the string inserted on click)
+     * of the menu item.
+     */
     action : function () {
       return this._action;
     },
+
+    /**
+     * The description of the menu item.
+     */
     desc : function () {
       return this._desc;
     },
+
+    /**
+     * The associated dom element of the
+     * menu item.
+     */
     element : function () {
       // already defined
       if (this._element !== undefined)
diff --git a/dev/js/src/hint/menu.js b/dev/js/src/hint/menu.js
index c579945..bf965d7 100644
--- a/dev/js/src/hint/menu.js
+++ b/dev/js/src/hint/menu.js
@@ -3,6 +3,10 @@
  */
 define(['menu', 'hint/item', 'hint/prefix'], function (menuClass, itemClass, prefixClass) {
   return {
+
+    /**
+     * Create new hint helper menu.
+     */
     create : function (hint, context, params) {
       var obj = Object.create(menuClass)
 	.upgradeTo(this)
@@ -25,10 +29,11 @@
 
       return obj;
     },
-    // Todo: Is this necessary?
-    context : function () {
-      return this._context;
-    },
+
+    /**
+     * The hint helper object,
+     * the menu is attached to.
+     */ 
     hint : function () {
       return this._hint;
     }
diff --git a/dev/js/src/hint/prefix.js b/dev/js/src/hint/prefix.js
index 84f785a..7586617 100644
--- a/dev/js/src/hint/prefix.js
+++ b/dev/js/src/hint/prefix.js
@@ -1,8 +1,17 @@
 define(['menu/prefix'], function (prefixClass) {
   return {
+
+    /**
+     * Create prefix object for the hint helper menu.
+     */
     create : function (params) {
-      return Object.create(prefixClass).upgradeTo(this)._init(params);
+      return Object.create(prefixClass).
+	upgradeTo(this)._init(params);
     },
+
+    /**
+     * Override the prefix action.
+     */
     onclick : function () {
       var m = this.menu();
       var h = m.hint();
diff --git a/dev/js/src/init.js b/dev/js/src/init.js
index cd99df1..5ef8dee 100644
--- a/dev/js/src/init.js
+++ b/dev/js/src/init.js
@@ -4,16 +4,38 @@
   'vc',
   'tutorial',
   'lib/domReady',
+  'hint/array',
+  'lib/alertify',
+  'api',
   'util'
 ], function (matchClass,
 	     hintClass,
 	     vcClass,
 	     tutClass,
-	     domReady) {
+	     domReady,
+	     hintArray) {
   domReady(function (event) {
     var obj = {};
 
     /**
+     * Replace Virtual Collection field
+     */
+    var vcname;
+    var input = document.getElementById('vc');
+    if (input) {
+      input.style.display = 'none';
+      vcname = document.createElement('span');
+      vcname.setAttribute('id', 'vc-choose');
+      vcname.appendChild(
+	document.createTextNode(
+	  document.getElementById('vc-name').value
+	)
+      );
+      input.parentNode.insertBefore(vcname, input);
+    };
+
+
+    /**
      * Add actions to match entries
      */
     var inactiveLi = document.querySelectorAll(
@@ -31,6 +53,7 @@
       });
     };
 
+
     /**
      * Toggle the alignment (left <=> right)
      */
@@ -41,8 +64,7 @@
 	toggle.setAttribute('title', 'toggle Alignment');
 	// Todo: Reuse old alignment from cookie!
 	var cl = toggle.classList;
-	cl.add('align');
-	cl.add('right');
+	cl.add('align', 'right');
 	toggle.addEventListener(
 	  'click',
 	  function (e) {
@@ -56,24 +78,11 @@
       };
     };
 
-    /**
-     * Init vc
-     */
-    var input = document.getElementById('vc');
-    if (input) {
-      input.style.display = 'none';
-      var vcname = document.createElement('span');
-      vcname.setAttribute('id', 'vc-choose');
-      vcname.appendChild(
-	document.createTextNode(
-	  document.getElementById('vc-name').value
-	)
-      );
-      input.parentNode.insertBefore(vcname, input);
 
-      /**
-       * Toggle the Virtual Collection builder
-       */
+    /**
+     * Toggle the Virtual Collection builder
+     */
+    if (vcname) {
       var vc;
       vcname.onclick = function () {
 	var view = document.getElementById('vc-view');
@@ -131,6 +140,22 @@
     // Todo: Pass an element, so this works with
     // tutorial pages as well!
     obj.hint = hintClass.create();
+
+    // Set hint array for hint helper
+    KorAP.hintArray = hintArray;
+
+    // Override KorAP.log
+    KorAP.log = function (type, msg) {
+
+      // Use alertify to log errors
+      alertify.log(
+	(type === 0 ? '' : type + ': ') +
+	  msg,
+	'warn',
+	5000
+      );
+    };
+
     return obj;
   });
 });
diff --git a/dev/js/src/match/info.js b/dev/js/src/match/info.js
index c47f5ae..b75e713 100644
--- a/dev/js/src/match/info.js
+++ b/dev/js/src/match/info.js
@@ -12,7 +12,7 @@
 	     matchTreeClass,
 	     matchTreeMenuClass) {
 
-  // TODO: Make this async
+  // Override 
   KorAP.API.getMatchInfo = KorAP.API.getMatchInfo || function () {
     KorAP.log(0, 'KorAP.API.getMatchInfo() not implemented')
     return {};
@@ -20,10 +20,11 @@
 
   var loc = KorAP.Locale;
 
-  /**
-   * Create new object
-   */
   return {
+
+    /**
+     * Create new match object
+     */
     create : function (match) {
       return Object.create(this)._init(match);
     },
@@ -44,6 +45,11 @@
       return this._match;
     },
 
+
+    /**
+     * Open the information view,
+     * if closed, otherwise close.
+     */
     toggle : function () {
       if (this.opened == true) {
 	this._match.element().children[0].removeChild(
@@ -64,7 +70,8 @@
 
 
     /**
-     * Retrieve and parse snippet for table representation
+     * Retrieve and parse snippet for table
+     * representation
      */
     getTable : function (tokens, cb) {
       var focus = [];
diff --git a/dev/js/src/match/infolayer.js b/dev/js/src/match/infolayer.js
index dbd93f9..0812f71 100644
--- a/dev/js/src/match/infolayer.js
+++ b/dev/js/src/match/infolayer.js
@@ -1,16 +1,26 @@
 /**
- *
- * Alternatively pass a string as <tt>base/s=span</tt>
- *
- * @param foundry
+ * Object representing information
+ * about a match's layer annotation.
  */
 define(function () {
-  var _AvailableRE = new RegExp("^([^\/]+?)\/([^=]+?)(?:=(spans|rels|tokens))?$");
+  var _AvailableRE =
+    new RegExp("^([^\/]+?)\/([^=]+?)(?:=(spans|rels|tokens))?$");
 
   return {
+    /**
+     * Create new match information
+     * object for one layer.
+     *
+     * Alternatively pass a string as
+     * <tt>base/s=span</tt>
+     *
+     * @param foundry
+     */
     create : function (foundry, layer, type) {
       return Object.create(this)._init(foundry, layer, type);
     },
+
+    // Initialize Layer 
     _init : function (foundry, layer, type) {
       if (foundry === undefined)
 	throw new Error("Missing parameters");
diff --git a/dev/js/src/match/table.js b/dev/js/src/match/table.js
index 7eba8a0..1a167d2 100644
--- a/dev/js/src/match/table.js
+++ b/dev/js/src/match/table.js
@@ -1,10 +1,21 @@
+/**
+ * Table representation of morphological
+ * annotations of a match.
+ */
 define(function () {
   var _TermRE = new RegExp("^(?:([^\/]+?)\/)?([^:]+?):(.+?)$");
   
   return {
+
+    /**
+     * Create new table view for a match
+     * based on a snippet string.
+     */
     create : function (snippet) {
       return Object.create(this)._init(snippet);
     },
+
+    // Initialize table based on snippet
     _init : function (snippet) {
       // Create html for traversal
       var html = document.createElement("div");
@@ -23,27 +34,49 @@
       return this;
     },
     
+
+    /**
+     * Length of the table (columns),
+     * aka the number of tokens
+     * in the snippet.
+     */
     length : function () {
       return this._pos;
     },
 
+    /**
+     * Get the token in the snippet
+     * At a given position.
+     *
+     * @param pos
+     */
     getToken : function (pos) {
       if (pos === undefined)
 	return this._token;
       return this._token[pos];
     },
-    
+
+    /**
+     * Get the annotation of a token
+     * in the snippet based on the position,
+     * the foundry, and the layer.
+     *
+     * @param pos
+     * @param foundry
+     * @param layer
+     */
     getValue : function (pos, foundry, layer) {
       return this._info[pos][foundry + '/' + layer]
     },
     
-    getLayerPerFoundry : function (foundry) {
-      return this._foundry[foundry]
-    },
-    
-    getFoundryPerLayer : function (layer) {
-      return this._layer[layer];
-    },
+    /*
+      getLayerPerFoundry : function (foundry) {
+        return this._foundry[foundry]
+      },
+      getFoundryPerLayer : function (layer) {
+        return this._layer[layer];
+      },
+    */
 
     // Parse the snippet
     _parse : function (children) {
diff --git a/dev/js/src/match/tree.js b/dev/js/src/match/tree.js
index b379b37..9722f94 100644
--- a/dev/js/src/match/tree.js
+++ b/dev/js/src/match/tree.js
@@ -1,5 +1,6 @@
 /**
- * Visualize span annotations as a tree using Dagre.
+ * Visualize span annotations as a tree
+ * using Dagre.
  */
 define(['lib/dagre'], function (dagre) {
   "use strict";
@@ -7,6 +8,9 @@
   var svgXmlns = "http://www.w3.org/2000/svg";
   var _TermRE = new RegExp("^(?:([^\/]+?)\/)?([^:]+?):(.+?)$");
 
+  // Node size
+  var WIDTH  = 55, HEIGHT = 20;
+
   // Create path for node connections 
   function _line (src, target) {
     var x1 = src.x,
@@ -22,24 +26,18 @@
   };
 
   return {
+
+    /**
+     * Create new tree visualization based
+     * on a match snippet.
+     */
     create : function (snippet) {
-      return Object.create(this)._init(snippet);
+      return Object.create(this).
+	_init(snippet);
     },
 
-    nodes : function () {
-      return this._next;
-    },
 
-    _addNode : function (id, obj) {
-      obj["width"] = 55;
-      obj["height"] = 20;
-      this._graph.setNode(id, obj)
-    },
-    
-    _addEdge : function (src, target) {
-      this._graph.setEdge(src, target);
-    },
-    
+    // Initialize the tree based on a snippet.
     _init : function (snippet) {
       this._next = new Number(0);
 
@@ -76,6 +74,25 @@
       return this;
     },
 
+    /**
+     * The number of nodes in the tree.
+     */
+    nodes : function () {
+      return this._next;
+    },
+
+    // Add new node to graph
+    _addNode : function (id, obj) {
+      obj["width"]  = WIDTH;
+      obj["height"] = HEIGHT;
+      this._graph.setNode(id, obj)
+    },
+    
+    // Add new edge to graph
+    _addEdge : function (src, target) {
+      this._graph.setEdge(src, target);
+    },
+    
     // Remove foundry and layer for labels
     _clean : function (title) {
       return title.replace(_TermRE, "$3");
@@ -148,7 +165,9 @@
       };
     },
 
-    // Get element
+    /**
+     * Get the dom element of the tree view.
+     */
     element : function () {
       if (this._element !== undefined)
 	return this._element;
@@ -183,26 +202,25 @@
 
 	  // Add node box
 	  var rect = group.appendChild(document.createElementNS(svgXmlns, 'rect'));
-	  rect.setAttributeNS(null, 'x', v.x - v.width / 2);
-	  rect.setAttributeNS(null, 'y', v.y - v.height / 2);
-	  rect.setAttributeNS(null, 'rx', 5);
-	  rect.setAttributeNS(null, 'ry', 5);
-	  rect.setAttributeNS(null, 'width', v.width);
-	  rect.setAttributeNS(null, 'height', v.height);
+	  rect.setAttribute('x', v.x - v.width / 2);
+	  rect.setAttribute('y', v.y - v.height / 2);
+	  rect.setAttribute('rx', 5);
+	  rect.setAttribute('ry', 5);
+	  rect.setAttribute('width', v.width);
+	  rect.setAttribute('height', v.height);
 
 	  if (v.class === 'root' && v.label === undefined) {
-	    rect.setAttributeNS(null, 'width', v.height);
-	    rect.setAttributeNS(null, 'x', v.x - v.height / 2);
-	    rect.setAttributeNS(null, 'class', 'empty');
+	    rect.setAttribute('width', v.height);
+	    rect.setAttribute('x', v.x - v.height / 2);
+	    rect.setAttribute('class', 'empty');
 	  };
 
 	  // Add label
 	  if (v.label !== undefined) {
 	    var text = group.appendChild(document.createElementNS(svgXmlns, 'text'));
-	    text.setAttributeNS(null, 'x', v.x - v.width / 2);
-	    text.setAttributeNS(null, 'y', v.y - v.height / 2);
-	    text.setAttributeNS(
-	      null,
+	    text.setAttribute('x', v.x - v.width / 2);
+	    text.setAttribute('y', v.y - v.height / 2);
+	    text.setAttribute(
 	      'transform',
 	      'translate(' + v.width/2 + ',' + ((v.height / 2) + 5) + ')'
 	    );
diff --git a/dev/js/src/match/treeitem.js b/dev/js/src/match/treeitem.js
index f096861..9a4b952 100644
--- a/dev/js/src/match/treeitem.js
+++ b/dev/js/src/match/treeitem.js
@@ -4,10 +4,20 @@
    */
 
   return {
+
+    /**
+     * Create new menu item
+     * for tree views.
+     */
     create : function (params) {
       return Object.create(itemClass)
 	.upgradeTo(this)._init(params);
     },
+
+    /**
+     * Get or set the content of the
+     * menu item.
+     */
     content : function (content) {
       if (arguments.length === 1) {
 	this._content = content;
@@ -15,17 +25,23 @@
       return this._content;
     },
     
-    // The foundry attribute
+    /**
+     * The foundry attribute of the menu item.
+     */
     foundry : function () {
       return this._foundry;
     },
 
-    // The layer attribute
+    /**
+     * The layer attribute of the menu item.
+     */
     layer : function () {
       return this._layer;
     },
 
-    // enter or click
+    /**
+     * Override click action of the menu item.
+     */
     onclick : function (e) {
       var menu = this.menu();
       menu.hide();
@@ -33,7 +49,8 @@
       if (menu.info() !== undefined)
 	menu.info().addTree(this._foundry, this._layer);
     },
-    
+
+    // Initialize tree menu item.
     _init : function (params) {
       if (params[0] === undefined)
 	throw new Error("Missing parameters");
diff --git a/dev/js/src/match/treemenu.js b/dev/js/src/match/treemenu.js
index 23341a4..16f6306 100644
--- a/dev/js/src/match/treemenu.js
+++ b/dev/js/src/match/treemenu.js
@@ -5,6 +5,16 @@
   "use strict";
 
   return {
+
+    /**
+     * Create new menu object.
+     * Pass the match information object
+     * and the item parameters.
+     *
+     * @param info The match info object
+     * @param params The match menu items
+     *   as an array of arrays.
+     */
     create : function (info, params) {
       var obj = Object.create(menuClass)
 	.upgradeTo(this)
@@ -19,6 +29,10 @@
       
       return obj;
     },
+
+    /**
+     * The match information object of the menu.
+     */
     info :function () {
       return this._info;
     }
diff --git a/dev/js/src/menu.js b/dev/js/src/menu.js
index 2bc356b..cc42855 100644
--- a/dev/js/src/menu.js
+++ b/dev/js/src/menu.js
@@ -1,10 +1,11 @@
 /**
- * Create scrollable drop-down menus.
+ * Scrollable drop-down menus with view filter.
  *
  * @author Nils Diewald
  */
 /*
  * TODO: space is not a valid prefix!
+ * TODO: Prefix should be case sensitive!
  */
 define([
   'menu/item',
@@ -13,7 +14,6 @@
 ], function (defaultItemClass,
 	     defaultPrefixClass) {
 
-  // Todo: This may not be necessary
   // Default maximum number of menu items
   var menuLimit = 8;
 
@@ -58,10 +58,15 @@
       delete this._prefix['_menu'];
     },
 
+
+    /**
+     * Focus on this menu.
+     */
     focus : function () {
       this._element.focus();
     },
 
+
     // mouse wheel treatment
     _mousewheel : function (e) {
       var delta = 0;
@@ -74,6 +79,7 @@
       e.halt();
     },
 
+
     // Arrow key and prefix treatment
     _keydown : function (e) {
       var code = _codeFromEvent(e);
@@ -122,7 +128,7 @@
 	e.halt();
 	break;
       case 8: // 'Backspace'
-	this._prefix.backspace();
+	this._prefix.chop();
 	this.show();
 	e.halt();
 	break;
@@ -214,22 +220,23 @@
     },
 
     /**
-     * Get the instantiated HTML element
+     * Get the associated dom element.
      */
     element : function () {
       return this._element;
     },
 
+
     /**
-     * Get the creator object for items
+     * Get the creator class for items
      */
     itemClass : function () {
       return this._itemClass;
     },
 
     /**
-     * Get and set numerical value for limit,
-     * i.e. the number of items visible.
+     * Get and set the numerical value
+     * for the maximum number of items visible.
      */
     limit : function (limit) {
       if (arguments.length === 1) {
@@ -239,6 +246,7 @@
       return this._limit;
     },
 
+
     /**
      * Upgrade this object to another object,
      * while private data stays intact.
@@ -252,6 +260,7 @@
       return this;
     },
 
+
     // Reset chosen item and prefix
     _reset : function () {
       this._offset = 0;
@@ -259,6 +268,7 @@
       this._prefix.value('');
     },
 
+
     /**
      * Filter the list and make it visible
      *
@@ -287,15 +297,23 @@
       return true;
     },
 
+
+    /**
+     * Hide the menu and call the onHide callback.
+     */
     hide : function () {
       this.active = false;
       this.delete();
       this._element.style.opacity = 0;
+      this._prefix.clear();
       this.onHide();
       /* this._element.blur(); */
     },
 
-    // To be override
+    /**
+     * Function released when the menu hides.
+     * This method is expected to be overridden.
+     */
     onHide : function () {},
 
     // Initialize the list
@@ -356,6 +374,7 @@
       this.item(this._list[this._list.length - 1]).noMore(bool);
     },
 
+
     /**
      * Get the prefix for filtering,
      * e.g. &quot;ve&quot; for &quot;verb&quot;
@@ -368,6 +387,7 @@
       return this._prefix.value();
     },
 
+
     // Append Items that should be shown
     _showItems : function (offset) {
       this.delete();
@@ -644,7 +664,9 @@
     },
 
 
-    // Length of the filtered list
+    /**
+     * Length of the filtered item list.
+     */
     liveLength : function () {
       if (this._list === undefined)
 	this._initList();
diff --git a/dev/js/src/menu/item.js b/dev/js/src/menu/item.js
index b80aa2a..b8e8808 100644
--- a/dev/js/src/menu/item.js
+++ b/dev/js/src/menu/item.js
@@ -34,16 +34,28 @@
     return this;
   },
 
+
+  /**
+   * Get or set the content of the meun item.
+   */
   content : function (content) {
     if (arguments.length === 1)
       this._content = document.createTextNode(content);
     return this._content;
   },
 
+  /**
+   * Get the lower cased field of the item
+   * (used for analyses).
+   */
   lcField : function () {
     return this._lcField;
   },
 
+
+  /**
+   * Get or set the information for action of this item. 
+   */
   action : function (action) {
     if (arguments.length === 1)
       this._action = action;
diff --git a/dev/js/src/menu/prefix.js b/dev/js/src/menu/prefix.js
index a4e428f..abcf66c 100644
--- a/dev/js/src/menu/prefix.js
+++ b/dev/js/src/menu/prefix.js
@@ -1,7 +1,13 @@
 define({
-  create : function (params) {
+
+  /**
+   * Create new prefix object.
+   */
+  create : function () {
     return Object.create(this)._init();
   },
+
+  // Initialize prefix object
   _init : function () {
     this._string = '';
 
@@ -15,8 +21,9 @@
     
     return this;
   },
+
   _update : function () {
-    this._element.innerHTML
+    return this._element.innerHTML
       = this._string;
   },
 
@@ -33,6 +40,10 @@
     return this;
   },
 
+
+  /**
+   * Get or set the activity status of the prefix.
+   */
   active : function (bool) {
     var cl = this.element().classList;
     if (bool === undefined)
@@ -43,31 +54,57 @@
       cl.remove("active");
   },
 
-  element : function () {
-    return this._element;
-  },
-
+  /**
+   * Check, if a prefix is given or not.
+   */
   isSet : function () {
     return this._string.length > 0 ?
       true : false;
   },
 
+  /**
+   * Get or set the prefix string.
+   */
   value : function (string) {
     if (arguments.length === 1) {
       this._string = string;
-      this._update();
+      return this._update();
     };
     return this._string;
   },
-  
+
+
+  /**
+   * Add string to prefix.
+   */
   add : function (string) {
     this._string += string;
-    this._update();
+    return this._update();
   },
 
+
+  /**
+   * Clear prefix
+   */
+  clear : function () {
+    this._string = '';
+    return this._update();
+  },
+
+
+  /**
+   * Action method.
+   * Expected to be overridden.
+   */
   onclick : function () {},
 
-  backspace : function () {
+
+  /**
+   * Remove the last character of the string
+   */
+  chop : function () {
+
+    // Prefix is long enough for backspace
     if (this._string.length > 1) {
       this._string = this._string.substring(
 	0, this._string.length - 1
@@ -77,9 +114,18 @@
       this._string = '';
     };
     
-    this._update();
+    return this._update();
   },
 
+
+  /**
+   * Get the associated dom element.
+   */
+  element : function () {
+    return this._element;
+  },
+
+
   /**
    * Return menu list.
    */
diff --git a/dev/js/src/tutorial.js b/dev/js/src/tutorial.js
index cacbe21..a028b8e 100644
--- a/dev/js/src/tutorial.js
+++ b/dev/js/src/tutorial.js
@@ -54,6 +54,10 @@
       return this;
     },
 
+
+    /**
+     * Initialize a search with a defined query.
+     */
     useQuery : function (e) {
       var q  = e.getAttribute("data-query");
       var ql = e.getAttribute("data-query-language");
@@ -74,6 +78,10 @@
       this.hide();
     },
 
+
+    /**
+     * Decorate a page with query event handler.
+     */
     initQueries : function (d) {
       var qs = d.querySelectorAll('pre.query.tutorial');
       var that = this;
@@ -85,6 +93,9 @@
     },
 
 
+    /**
+     * Show the tutorial page embedded.
+     */
     show : function () {
       var element = this._element;
       if (element.style.display === 'block')
diff --git a/dev/js/src/vc.js b/dev/js/src/vc.js
index 1bb3b15..1aed3cf 100644
--- a/dev/js/src/vc.js
+++ b/dev/js/src/vc.js
@@ -138,6 +138,7 @@
       return obj;
     },
 
+
     /**
      * Create and render a new virtual collection
      * based on a KoralQuery collection document 
@@ -171,6 +172,10 @@
       return this;
     },
 
+
+    /**
+     * Clean the virtual document to uspecified doc.
+     */
     clean : function () {
       if (this._root.ldType() !== "non") {
 	this._root.destroy();
@@ -179,6 +184,7 @@
       return this;
     },
 
+
     /**
      * Get or set the root object of the
      * virtual collection.
@@ -206,6 +212,7 @@
       return this._root;
     },
 
+    
     /**
      * Get the element associated with the virtual collection
      */
diff --git a/dev/js/src/vc/doc.js b/dev/js/src/vc/doc.js
index 2635b2f..f04b445 100644
--- a/dev/js/src/vc/doc.js
+++ b/dev/js/src/vc/doc.js
@@ -10,10 +10,10 @@
 
     /*
       var fieldMenu = menuClass.create([
-      ['Titel', 'title', 'string'],
-      ['Untertitel', 'subTitle', 'string'],
-      ['Veröffentlichungsdatum', 'pubDate', 'date'],
-      ['Autor', 'author', 'string']
+        ['Titel', 'title', 'string'],
+        ['Untertitel', 'subTitle', 'string'],
+        ['Veröffentlichungsdatum', 'pubDate', 'date'],
+        ['Autor', 'author', 'string']
       ]);
       
       fieldMenu.limit(5);
@@ -417,29 +417,37 @@
 
     // Click on the match operator, show me the menu
     _changeValue : function (e) {
-      // TODO: Just kidding - this is temporary!
 
+      // Show datepicker
       if (this.type() === 'date') {
 	var dp = KorAP._vcDatePicker;
 
 	var v = this.value();
 	if (v !== undefined) {
-	  var d = v.split('-');
-	  dp.select(parseInt(d[0]), parseInt(d[1]), parseInt(d[2]));
+
+	  var d = v.split('-', 3);
+	  d[0] = parseInt(d[0]);
+	  if (d[1]) d[1] = parseInt(d[1]);
+	  if (d[2]) d[2] = parseInt(d[2]);
+
+	  // Select values
+	  dp.select(d[0], d[1], d[2]);
 	};
 
 	var that = this;
+
 	dp.onclick(function (selected) {
 
 	  // There are values selected
 	  if (selected['year']) {
-	    var v = selected['year'];
+	    var v = '' + selected['year'];
 	    if (selected['month']) {
 	      v += '-';
 	      v += selected['month'] < 10 ? '0' + selected['month'] : selected['month'];
-	      if (selected['day'])
+	      if (selected['day']) {
 		v += '-';
 		v += selected['day'] < 10 ? '0' + selected['day'] : selected['day'];
+	      };
 	    };
 	    that.value(v);
 	    that.update();
@@ -452,12 +460,22 @@
 	  );
 	});
 
+	// Get element of the date picker
+	var dpElem = dp.show();
+
 	this._element.insertBefore(
-	  dp.show(),
+	  dpElem,
 	  this._valueE
 	);
+
+	dpElem.focus();
+	dpElem.addEventListener('blur', function (e) {
+	  // Remove datepicker
+	  that._element.removeChild(this);
+	});
       }
       else {
+	// TODO: Just kidding - this is temporary!
 	this.value(window.prompt('Enter new value'));
 	this.update();
       };
diff --git a/dev/js/src/vc/menu.js b/dev/js/src/vc/menu.js
index d305960..17ad073 100644
--- a/dev/js/src/vc/menu.js
+++ b/dev/js/src/vc/menu.js
@@ -4,9 +4,17 @@
 define(['menu', 'vc/item'], function (menuClass, itemClass) {
   return {
     create : function (params) {
-      return Object.create(menuClass)
+      var obj = Object.create(menuClass)
 	.upgradeTo(this)
-	._init(itemClass, undefined, params)
+	._init(itemClass, undefined, params);
+      obj.limit(6);
+
+      // This is only domspecific
+      obj.element().addEventListener('blur', function (e) {
+	this.menu.hide();
+      });
+
+      return obj;
     },
 
     /**