HTTP is short for “HyperText Transport Protocol,” version 1.1 of which was introduced in 1997. HTTP 1.1 is still the most widely used version of HTTP, although it seems that this will change in the coming years with the introduction of HTTP/2. The switch to HTTP/2 is necessary because HTTP 1.1 no longer fits the way people use the Internet today.
Before we go into the details of the difference between HTTP 1.1 and HTTP/2, it is good to understand how HTTP works. HTTP makes it possible to send requests and get them responded to. Based on a request, the typing of the URL of a website, the called server then displays the website.
Problems with the use of HTTP 1.1
HTTP 1.1 is not the first version of HTTP. The first version bore the name HTTP 0.9 and was introduced back in 1991, six years before HTTP 1.1 was introduced. The basis of HTTP 0.9 is still used in HTTP 1.1 and HTTP/2. Although HTTP 1.1 was happily used by website owners and web hosting providers for many years, more and more problems arose. For example, HTTP 1.1 allowed only one request to be processed per connection. This meant that four or five connections were needed to load four or five images. Not efficient at all!
Also, more and more cookies are being used, one of which is sent per connection. Cookies make it possible to track visitors’ use of the website. These cookies are now so large that they slow down the connection and thus the website.
Introduction of the new HTTP/2
To provide a solution to these problems, Google, Microsoft, and Facebook introduced the new HTTP/2. HTTP/2 allows many more requests to be processed within the same time, as was possible with HTTP 1.1. The server itself can determine which requests should be processed first. Besides, headers, which contain information about the established connection, are no longer sent as separate entities. The headers are now compressed per connection, which makes a website faster.
This article describes the basic differences between HTTP 1.1 and HTTP/2. However, there are several other, much more technical differences to notice when looking at both HTTP versions. You can find more information about this on the Internet.