Reliability Monitor tracks the history of your computer — any time an application crashes, hangs, or Windows gives you a blue screen of death. You can click on each day that has a crash, then go back in the list to before all the crashes started and figure out what was installed to make things break… If you open up the Action Center, you can use the “View reliability history” link to get there, but we’d recommend opening the start menu or start screen and searching for “reliability”, which is probably faster.
It also tracks other important events, like when software is installed, or Windows Updates loads a new patch. The top part of the view is arranged into either days or weeks, depending on what you select.
It’s an extremely useful way to do some analysis when you’re asked to fix somebody else’s computer.
Some of them are driver installations so don't represent actual Windows updates, but many of the are updates to Windows "apps" (Skype, Phone, Solitaire, Twitter, etc.).
Are these updates considered to be different from "Windows updates"?
You can use the index to help evaluate the reliability of your computer by reviewing the reported application failures, Windows failures, Miscellaneous failures, Warnings, and Information.
Any change you make to your computer or problem that occurs on your computer affects the stability index.