Information Design
Information Design is really not about the Protocol Stack - nor Twitter. However Information Design is where you define certain aspekts of an Information Environment. In my view this is the startegy, scope and structure of a website. From a technical viewpoint I think the Protocol Stack is essential when you learn Internet Technologies.
An new way of sharing Information is through Social Media such as Twitter, LinkedIn or Slideshare to mention a few. These are not the most used, but all three suits my need to communicate through the Social Information Flow.
Slideshare
My favorite cloud container of presentations is Slideshare - where you can promote your work and see others. Its a nice source of information for those who like to use PowerPoint or Keynote.