Browser Cache
Browser cache (or Temporary Internet Files) are files saved locally. When you visit a site your browser will check to see if it already has a copy of the page and all its files (buttons\icons, photos, JavaScript etc) cached already. If so and the file hasn’t been modified, instead of downloading again your browser will instead use the local cached copy.
It’s faster to get a file to load from your hard disk compared to downloading it again from the internet. For example on a first visit to our website the logo will be downloaded… visiting a different page within the same site means the cached copy of this file won’t have to be download again.
Cache is usually set at a certain size in your web browser. Once the cache is full and you visit new sites, the oldest items stored will be removed.
Because you may be looking at a saved copy of a website any changes recently made could be missed. Clearing your cache forces the browser to load the latest copy of the web page.
F5, Ctrl+R or the refresh button reloads the page without clearing the browser’s cache.
Ctrl+F5 redownloads the page (on most Windows and Linux browsers). It is used to force an update, bypassing any cache to display the very latest version. It’s safe and simple to use.
Caching Plugins for WordPress
WordPress runs off a database and requests fresh information about a page every visit. Instead of finding and loading the data, caching plugins will cache your WordPress posts, pages and any other dynamic content as static files. This means database requests to the server will be lower, which will in turn make your pages load faster. Visitors (including new ones) will see a cached copy.
Most caching plugins will clear the cache when a post, page or comment is published. You may find that not all changes (for example amendments to a theme) will update. In this case the plugin will normally have a Delete Cache (or similar) button to ‘manually’ clear the cache.
It is useless to clear your site’s WordPress cache if you don’t also clear your browser cache.