HTTP compression is a technique used to reduce the amount of data transmitted between a web server and a web browser. It works by compressing the data before it is sent and then decompressing it on the other end. This compression reduces the size of the data that needs to be transmitted, which can result in faster load times and reduced bandwidth usage. HTTP compression is typically used for text-based content, such as HTML, CSS, and JavaScript, but it may not be suitable for all types of data.