CIS 11 -- Introduction to Information Systems

An Introduction to Logic Gates

This web site provides a brief description of logic gates and defines a few of the common logic gates found in simple digital circuits. 

The navigation bar provides links to pages where you can view the symbol, truth table, and animation of particular logic gates and a sample circuit.

Digital Logic

Keep in mind that computers work on an electrical flow where a high voltage is considered a 1 and a low voltage is considered a 0.  Using these highs and lows, data are represented.  Electronic circuits must be designed to manipulate these positive and negative pulses into meaningful logic.

Logic gates are the building blocks of digital circuits.  Combinations of logic gates form circuits designed with specific tasks in mind.  For example, logic gates are combined to form circuits to add binary numbers (adders), set and reset bits of memory (flip flops), multiplex multiple inputs, etc.