Cache is a temporary memory that stores copies of already-processed data or pages, so on the next visit they are served instantly instead of being recalculated or re-downloaded from scratch.
How cache works
The first time you visit a page, the server generates it and the browser downloads images, styles and scripts. The cache saves these elements: on the next visit they are taken from memory, the page appears much faster and the server does less work. It is the same principle that lets a PWA work offline.
Types of cache
- Browser cache: stores resources on the user's device.
- Server cache: keeps already-generated pages on the hosting side.
- CDN cache: serves content from servers near the user.
Cache and performance
A good cache strategy cuts load times, improves Core Web Vitals and lightens the hosting load. It must be managed well, though: if it does not refresh at the right time, users may see old content. In our hosting we configure cache to combine speed with always-fresh content.
Related terms: CDNPWAHosting
Frequently asked questions
What does clearing the cache mean?
It means deleting the saved temporary copies, so the browser or server reloads the most recent version. It is useful when you have updated a site but keep seeing the old version.
Does cache slow down or speed up a site?
It speeds it up. By serving ready-made content from memory, it reduces load times and server load. It can only cause problems if it is not refreshed correctly.
Why do I sometimes not see changes to a site?
It is often the cache: the browser or server shows you a saved copy. Clearing the cache or forcing a reload will show the updated version.