Page Monitor is a browser extension that can monitor webpages for you. It will notify you when the contents of a page change. This way, you will be able to stay on top of the most important information on the web. If you want to know what's on the other side of the globe, or if a product has changed its price, you can use Page Monitor to keep track of everything.

You don't have to do anything: just install the extension, and then your browser will be monitoring the webpages for you. If there is a change, it will display a notification on its icon.