Especially when searching, the cache is a way for browsers and search engines to save HTML pages and images from reducing bandwidth and holding them in the browser for later use.
A web designer may ask you to perform a forced cache clear (clear the browser's history) to see updated changes to the website.
With browser caching, the first time a visitor visits a website, the browser stores the assets it set up in the original browser cache in a separate cache set. Browser caching still requires new visitors to first retrieve assets from the site's server.
Browser caches can be told to update by a website, by a website specifying the cache period, and also by forcing a clear when updates are made.
A server-side cache is a kind of reverse proxy that acts on behalf of the website hosting service
and intercepts and serves visitors as soon as they reach their origin. When a request is made to the same web address as the URL, the web cache uses the previously stored response to send a new request from the source server.
A server-side cache setup can serve multiple visitors with the same cache without having to make a query to your original server, significantly reducing the load on the servers, which is useful for repeat visitors and even speeds up the first viewing of a website.
With dynamic websites using PHP
, such as WordPress
, when a page is loaded each time PHP compiles the site and outputs HTML to the web browser. The request, if run on a shared web hosting
a dedicated server, or cloud hosting
, uses Ram & CPU to compile the page and deliver it. With many connections, this can cause the CPU & RAM usage to spike.
Implementing server-side caching causes this load to disappear, caching the HTML output on the server-side.
PHP also has a module called OPCache, which can help speed up PHP page builds, by caching PHP queries and returning cache files for matching results.
Here at WPOwl, we use server-side caching in NGINX
, and we also use OPCache in PHP.
A web cache is used to reduce the time between the client's request for a file or resource and its actual arrival and response time.
According to a recent study by YUI, web caching can increase speed by up to 300%. When it comes to loading speed, it pays to do things as quickly as possible, and you can dramatically reduce your website loading times by using both browser and server caches.
It is worth remembering that by implementing a web cache, you are not only making your website faster but also making it more powerful and equipping it to handle high traffic peaks.