March 31, 2000: Here's Dave Winer on What is a Web Application?.

But, um, what is a web app? The definition starts becoming impossibly broad.. is all that separates a "web" app from a traditional app the fact that it's based on a markup language? Is it that it speaks http?

The exciting things to me about "web apps" are:

• They're free ;)
• They are accessible to many authors. By opening application development to non-C-coders, we inevitably increase the pace of interface innovation (heh.. so we can have lots of Buffy the Vampire Slayer skins all over our apps ;)
• They are standards-based so that I can access them from most anywhere.
• They are "of" the net. In other words, they let me do things I couldn't do with non-networked apps.

The interesting thing about that second point is that really all I care about is having my data on the network (and in an open format). That's why I see xdrive as much more useful than halfbrain even though it's ostensibly more limited and why I really like the idea of an XML-RPC-accessible world.