If a website has a Feed/RSS function, it can tell us whether a website/webpage has been updated or not. Conversely, if some sites don't offer or turn off the RSS functionality (this has become a trend), you can use some online tools or PC software such as Website-Watcher to meet the same requirements, without having to do that manually through a web browser.

The uptime reliability of websites or servers (for example: file servers, mail servers, routers...) is crucial for web site operators, sometimes even fatal (because that seriously affects visitors' user experience). At the same time, this is also one of the two most important and basic measures to a server's quality (the other one is visiting speed).