The XML Suite
The Extensible Markup Language (XML) is a general-purpose markup language. For any information about XML, the reference url is www.w3.org.
The property list Suite
Smile implements an XML Suite into AppleScript, based on the libxml2 and libxslt Open Source projects. Smile's XML Suite works with references to the nodes rather than with data: this enables to use the XML Suite with possibly very large XML files. The representation of the XML tree follows the DOM model. The XML Suite implements XPATH and XSLT.
Documentation and examples of the XML Suite commands are included in the XMLLib.osax dictionary.
Also available is a short XML tutorial for XMLLib.osax which works on a real XML file (the periodic chart of the chemical elements). You can simply visit the tutorial or run it on your machine.
Property list is a simple XML format (PropertyList-1.0.dtd - a Document Type Definition) designed by Apple for OSX as a format for storing lists of key-value pairs (p-list stands for Properties list). Most applications store their Preferences as property list files.
A property list can store the following elementary classes of AppleScript variables: string, integer, real, true, false, date. It can also store lists ("array" tag in a p-list) and records ("dict" tag), (in other terms, lists of key-value pairs). Moreover, The p-list also defines a "data" field, which uses base64 to store arbitrary kinds of data.
NB: The plist Suite provides a favorable framework to define fast lookup tables. A lookup table (sometimes also called a map, an associative array, or a dictionary) is a list of key-value pairs, supporting the lookup operation which consists in retrieving a value, being given its key. The p-list's lookup operation is very fast and its speed does not depend on the p-list's size.