Its a stupid question to ask. Is HTTP 1.0 still used by any client or server? its because I am working on a proxy server program that requires HTTP 1.1
Short answer: Yes. Long answer: You can't say that HTTP 1.0 is extinct. Basically there are a lot of tools that are coded using 1.0 so if you are working on a proxy you have to support both 1.0 and 1.1. This document has some key differences between 1.0 and 1.1, it's important for you to see how 1.0 dealt with cache, and how 1.1 does.