How do protocols like HTTP/2 improve web performance?

HTTP/2 improves web performance by enabling multiplexing, header compression, and server push, thus reducing latency and speeding up page loads.

HTTP/2, or Hypertext Transfer Protocol version 2, is a major revision of the HTTP network protocol used by the World Wide Web. It introduces several key features that significantly enhance web performance. One of the most important is multiplexing, which allows multiple requests and responses to be sent simultaneously over a single TCP connection. This is a significant improvement over HTTP/1.1, which requires a new TCP connection for each request/response pair, leading to increased latency and slower page loads.

Another significant feature of HTTP/2 is header compression. HTTP headers often contain a lot of redundant data, which can slow down web performance. HTTP/2 uses a compression algorithm called HPACK to reduce the size of these headers, thereby reducing the amount of data that needs to be transferred and speeding up page loads.

HTTP/2 also introduces a feature called server push. This allows a server to send resources to a client before the client requests them, which can significantly speed up page loads. For example, if a client requests an HTML document, the server can also send the CSS and JavaScript files that the document references, without waiting for the client to request them. This can reduce the number of round-trip times (RTTs) required to load a page, thereby improving web performance.

In addition to these features, HTTP/2 also includes other enhancements such as stream prioritisation, which allows more important requests to be sent before less important ones, and flow control, which prevents a sender from overwhelming a receiver with data. These features, combined with the ones mentioned above, make HTTP/2 a powerful tool for improving web performance.

It's important to note that while HTTP/2 can significantly improve web performance, it's not a silver bullet. Other factors, such as the quality of a website's code and the speed of a user's internet connection, can also have a significant impact on web performance. However, by enabling multiplexing, header compression, and server push, HTTP/2 can make a substantial contribution to reducing latency and speeding up page loads.