Vocabulary

• Web 1.0  -  "basics" - read only, data silos
• Web 2.0  -  Read / write web = community (download AND upload info, data, projects), interactivity, participatory, interconnectivity, ex of top level = E-Bay and Wikipedia (exist only on the net)
•  Web 3.0  -  "Machines" (natural language searching, open technology, high level of reliability, cloud computing, artificial intelligence.
•  Web 4.0 = merging of 2 & 3 = "Learning Web"

• avatars - "A pictorial representation of a participant in a ... chat environment. The avatar is chosen by the user and may look like a bird, a fish, or some other colorful character.*"  Avatars may provide a "safe" way for students to participate online.
• blog - short for web + log.
• collaborative - working together on something
• Creative Commons - flexible copyright protection that allows the author / creator to specify who can use what, how
• Folksonomies - group tagging or informal classification of information
• IM - Instant Messaging or chat. Real time communication typically using text. Meebo: web-based IM
• mashups - content from different sources that looks seamless when using "web application hybrids" for example Sketchup and Google Earth.
• open source - "refers to practices in production and development of software by a ... community (typically volunteers from many organizations) rather than a single vendor. The source code of open source software is free and available to anyone who would like to use it or modify it for their own purposes. This allows an organization to add a feature itself rather than hope that the vendor of a proprietary product will implement its suggestion in a subsequent release.*"
• participatory - users of web sites adding their own perspective
• rss - really simple syndication. A fast and easy way for information to get "pushed" to you. You'll need an aggregator or feed collector such as Bloglines or Goggle Reader which collects all the new content. Browsers such as Safari and Explorer can also do it for you too.  One page instead of hundreds!
• social network -  a place on the web where folks create connections with friends and colleagues. (for example Facebook, MySpace, Friendster)
• tagging - assigning specific "key word" or tags to the site you created (metatagging) or bookmarked. Some tags proportionately change size with the number of identical tags, for an example see Presidential Cloud. 
• virtual  classroom - required in some states for high school gradution
• virtual community - a group sharing common concern/problem/passion. Geographical location is not relevant
• widgets - bits of multimedia content customized (blog bling)
• wiki - group editing of a web site

Feel free to suggest other items to include.