The browser cache stores all the web pages and images downloaded on to the computer to allow faster access and reduce the downloading bandwidth when revisiting a website.

Type “about:cache” on your Firefox address bar to view the cached files.  There are 3 types of cache for allocating the files…

1) Memory cache device, stores all the files which are downloaded per session into your computers RAM (or temporary memory).  This means after you restart your Firefox, the files will be cleared out.

2) Disk cache device, stores all the files into your hard disk drive.  This is some file location in your computer, for example within your Windows C:\ drive.  These are available after restarting the Firefox and accessible without an internet connection.

3) Offline cache device, stores all the files which can be used for offline browsing.  Typically it is empty, but is targeted for upcoming offline applications.  Watch this space.

One useful tip to improve FIrefox performance is to disable disk cache (or set Tools > Options > Advanced > Network > Offline Storage: Use 0Mb).  What this means to to purely rely on the RAM memory for cached data, and not read from the disk.  A simple concept: memory read speed is faster than disk read speed.

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