google help (+rep)

[Firehorse]

These are the easiest things to remove ever, you just have to boot into safe mode and work out where it stores it's DLLs, .exe and then do a registry cleanup with CCleaner. Generally they're stored in %AppData%\RANDOM-STRING.exe

These are usually because your system isn't up to date or you're using an outdated/crap browser.

They can still find a way to bounce back

[Recursion]

They can still find a way to bounce back

Never had that issue myself.