Hi Harris, I have disabled them in my Preferences:

When Blender crashes, you can got to Recover > Auto Save. The .blend1 (.blend2….) are from when you Saved previously. So, if you Svae your file 5 times, the last Save will be your .blend and (if enabled) the Save before that will be a .blend1, and so on…
Wayne actually wrote an article on this:
https://blog.cgcookie.com/what-is-a-blend1-file-and-do-you-really-need-them/
It’s a personal preference, of course, but I prefer just using Incremental Saves, which stay available, until I Delete them.