Discrete components are individual electronic devices, such as resistors, capacitors, LEDs, and transistors. You connect the components as you build circuits. An integrated circuit (IC) contains anywhere from a few dozen to many billions (yes — billions!) of circuit components packaged in a single device that can fit into the palm of your hand.
The components in an IC aren't just randomly thrown together in the package. They are connected to form a miniature circuit that performs one or more functions, such as counting or adding two numbers. Among the most complex ICs are the microprocessors that do most of the work involved in running your laptop, tablet, smartphone, and other devices.
Microprocessors — which contain millions (or billions) of tiny transistors and other components — perform many functions and are often called the brains of computing.
