555 Timer 

555 Timer is an integrated circuit (chip) which is broadly used in electronics. Its use cases range from Square wave generation to some sort of analog to digital conversion. It can be found at electronics since several decades ago.

Pronounced as Five-Five-Five Timer.

555 Timer can do what an electronics nerd wants to do, Square, Sine, Triangle, you name it.

555 Timer by alienozi May 8, 2018