[deanhills]

Thanks for the detailed response @Mashiro.  Regarding:

The name basically already says what it does mem = memory, cached well, its cached... both means memory cached. Basically you use as much free RAM as possible to speed up your web applications like websites and other stuff.

Would there be any negative consequences for not installing this process? Apart from being slower of course.

Reason why I was anti and said NO was that I'm worried when creating posts and making changes to my WordPress sites that caching would be an issue for being able to see the changes immediately.