What is the difference between HTTP/1.1 and HTTP/2? What was added and what was changed in HTTP/2?

HTTP/2 is an evolution of the HTTP/1.1 protocol aimed at improving performance and data transfer efficiency.

Main differences and improvements of HTTP/2 compared to HTTP/1.1:

• Multiplexing: HTTP/2 allows multiple requests to be sent and responses to be received simultaneously over a single TCP connection without blocking, unlike HTTP/1.1, where requests are processed sequentially or with limitations (pipelining).

• Binary protocol: HTTP/2 uses a binary format for data transmission instead of text, which simplifies parsing and reduces errors.

• Header compression: HTTP/2 implements the HPACK mechanism for efficient compression of HTTP headers, reducing the amount of data transmitted.

• Request prioritization: The client can specify priorities for requests, allowing the server to allocate resources optimally.

• Server push: The server can proactively send resources to the client without an explicit request, improving page load times.

Overall, HTTP/2 enhances loading speed, reduces delays, and increases the efficiency of network resource utilization compared to HTTP/1.1.