Question: > 
> HTTP/1.1 has served the Web well for more than fifteen years, but its
>  age is starting to show.
> 
> 
> 

Can anybody explain what is the **main difference** between HTTP 1.1 and 2.0?

Is there any change in the transport protocol?

Answer: 
HTTP/2 supports queries multiplexing, headers compression, priority and more intelligent packet streaming management. This results in reduced latency and accelerates content download on modern web pages.

[More details here.](https://daniel.haxx.se/http2/)
HTTP 2.0 is a **binary** protocol that multiplexes numerous streams going over a single (normally TLS-encrypted) TCP connection.

The contents of each stream are HTTP 1.1 requests and responses, just encoded and packed up differently. HTTP2 adds a number of features to manage the streams, but leaves old semantics untouched.