cheat sheets.

Commmon DOM functions, grouped by task (from http://www.wait-till-i.com)

--[Reaching Elements in a Document]--
  document.getElementById('id'): Retrieves the element with the given id as an
    object 
  document.getElementsByTagName('tagname'): Retrieves all elements with the
    tag name tagname and stores them in an array-like list 
--[Reading Element Attributes, Node Values and Other Data]--
  node.getAttribute('attribute'): Retrieves the value of the attribute with
    the name attribute 
  node.setAttribute('attribute', 'value'): Sets the value of the attribute
    with the name attribute to value 
  node.nodeType: Reads the type of the node (1 = element, 3 = text node) 
  node.nodeName: Reads the name of the node (either element name or #textNode) 
  node.nodeValue: Reads or sets the value of the node (the text content in the
    case of text nodes) 
--[Navigating Between Nodes]--
  node.previousSibling: Retrieves the previous sibling node and stores it as
    an object. 
  node.nextSibling: Retrieves the next sibling node and stores it as an
    object. 
  node.childNodes: Retrieves all child nodes of the object and stores them in
    an list. here are shortcuts for the first and last child node, named 
    node.firstChild and node.lastChild. 
  node.parentNode: Retrieves the node containing node. 
--[Creating New Nodes]--
  document.createElement(element): Creates a new element node with the name
    element. You provide the name as a string. 
  document.createTextNode(string): Creates a new text node with the node value
    of string. 
  node.cloneNode(bool): Creates and returns a copy (clone) of node. If bool is
     true, the clone includes clones of all the child nodes of the original. 
  node.appendChild(newNode): Adds newNode as a new (last) child node to node. 
  node.insertBefore(newNode,oldNode): Inserts newNode as a new child node of
    node before oldNode. 
  node.removeChild(oldNode): Removes the child oldNode from node. 
  node.replaceChild(newNode, oldNode): Replaces the child node oldNode of node
    with newNode. 
  element.innerHTML: Reads or writes the HTML content of the given  element as
    a string—including all child nodes with their attributes and text content.
--[Known browser quirks:]--
  getAttribute and setAttribute are not reliable. Instead, assign the property
  of the element object directly: obj.property = value. Furthermore, some
  attributes are actually reserved words, so instead of class use className and
  instead of for use HTMLfor.
  Real DOM compliant browsers will return linebreaks as text nodes in the
  childNodes collection, make sure to either remove them or test for the
  nodeType.