# What is a logic Circuit?

A **Logic circuit** uses two logic levels to transfer the information. A hight logic level or “1” and a low logic level or “0”. The Logic circuits are made of digital elements such as the AND gate, the OR gate, the NOT gate and a combinations of them.

These combinations give way to other types of digital elements such as logic gates, among others.

– NAND gate

– NOR gate

– Exclusive OR gate

– Mutiplexors

– Demultiplexors

– Decoders

– Encoders

– Memories

– Flip-flops

– Microprocessors

– Microcontrollers

– Etc.

Modern digital electronics is used to perform many functions. While digital electronic circuits might seem very complex, actually they are built with a very large number of very simple circuits.

In Digital electronics the information is transmitted between circuits in a binary form (zeros and ones). The binary information is represented in the form of:

- “0” and “1”,
- “Open” or “Closed” (switch)
- “On” and “Off”
- “False” or “True”, etc..

A** logic circuit** can be represented in many ways. In the following circuits the lamp can be turned on or off, depending on the switch position.

A truth table is a tabular listing of all possible states of the switches (inputs) that affect the circuit and their corresponding output values.