Google gears is an Open Source browser extension (addon) that lets web application work offline. It provides developers with a tool for creating Web applications that can be used Offline too. Web application users can work offline after installing the browser extension and data will be automatically synchronized when they are back online.
There are many applications that use Google Gears for example Remember the Milk. Once you enable offline access using Google Gears, you can work on the application even when you are not connected to internet and data will be synchronized when you come back online.
