APPCACHE file extension

This file is used by web browsers to allow access to web applications without a network connection. It stores such resources used by applications as images (PNG, GIF), CSS files, and JS files. With these files, you can use web applications even without an Internet connection. APPCACHE files include four optional sections: CACHE, NETWORK, FALLBACK, and SETTINGS. The first section includes all resources that need to be downloaded and saved locally. The second section stores all URLs that cannot be cached. The third section lists replacements for network URLs which are used if there is no Internet connection. And the fourth section defines preferences for application cache behavior.