Pronounced "browser cash." A temporary storage area in memory or on disk that holds the most recently downloaded Web pages. As you jump from Web page to Web page, caching those pages in memory lets you quickly go back to a page without having to download it from the Web again. In order to ensure that the latest page is displayed, the browser compares the dates of the cached page with the current Web page. If the Web page has not changed, the cached page is displayed immediately. If the Web page has changed, it is downloaded, displayed and cached.
When you quit the browser session, the cached pages are stored on disk. Settings in your Web browser let you set the amount of space to use for the cache, which is essentially a disk folder, and the length of time to hold the pages. See Web cache