An infinite loop doesn't crash a computer, at least it takes 100% CPU

An infinite loop causes a section of code to loop indefinitely. Beyond that, whatever the section of code does is entirely up to the programmer. There is nothing inherently malicious about infinite loops.

aside from ctrl+c, how do you terminate an infinite loop?

Inside the code or from the OS? Inisde the code you can use "break;", in the SO you can 'kill' the task with taskmaneger (ctrl+alt+del -> tasks).