Pressing these keys on a Commodore 64/128 will tell the computer to perform a warm boot. This key combination usually doesn't affect the contents of memory, so loaded programs will still be present. (They probably won't be able to re-run correctly if they rely on many higher functions of the computer.)
This is the all-purpose Commodore problem solver key combination. Run/Stop is similar in use and functionality to the CTRL+C key combination on UNIX and UNIX-like systems. A Run/Stop Restore will break out of almost any program, misbehaving or not. Memory corruption, however, is almost guaranteed with more complex software.
If your software is behaving badly, switch the computer off, then on. (Yes, memory corruption has been known to linger EVEN after an SYS 64760.)