The old web was a pure pull medium, because users had to visit each web site in order to find out what (if anything) had changed. However, businesses and advertisers in particular love push technologies – where content is delivered to the user when it becomes available. RSS is an interesting mix between the two extremes, neither of which could actually work in our information-overloaded and advertising-saturated world. RSS is basically a filtered push – the user subscribes (pulls in) to channels that he/she likes, and after that content is delivered automatically.
A very interesting read about what RSS is, how it works, and where it is going in the future. It is definitely worth the read if you’re a designer/coder.
Wandering the Interwebs 