The primary function of the cerebellum is to maintain posture and balance. When we jump to the side, reach forward, or turn suddenly, it subconsciously evaluates each movement. The cerebellum then sends signals to the cerebrum, indicating muscle movements that will adjust our position to keep us steady.
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
acu.exe is a process belonging to the Atheros Client Utility (ACU) which is a program that allows additional for configuration and diagnostic functions on HP and Toshiba's range of wireless communication devices. This program is a non-essential process, but should not be terminated unless suspected to be causing problems.