Welcome to Electronics Done Quick where I try to explain the most basic components used in electronics as fast and as simple as possible.
The operational amplifier is arguably the most useful single device in analog electronic circuitry. With only a handful of external components, it can be made to perform a wide variety of analog signal processing tasks.
This is a companion discussion topic for the original entry at https://community.robotshop.com/tutorials/show/electronics-done-quick-8-operational-amplifiers