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As a website owner, you want your website to be fast, efficient, and accessible to as many users as possible. One of the best ways to achieve this is by using HTTP caching headers. These headers tell web browsers and other HTTP clients how to cache and serve content from your website.
This article highlights important information on HTTP caching headers and associated CDN behavior. In case you are looking for in-depth information on the role of HTTP cache headers in the modern web, here’s everything you need to know.
How caching worksWhen a browser requests a file from a server, the server responds with the file and some cache headers. The browser then caches the file based on these headers. The next time the browser requests the same file, it checks its cache to see if it already has a copy. If it does, and the file hasn’t expired, the browser serves the cached version of the file. If the file has expired or if the browser has been told not to cache it, the browser requests a fresh copy of the file from the server.