logic gates

there are 6 different logic gates:

AND gate

A	B	A.B
0	0	0
0	1	0
1	0	0
1	1	1

The AND gate is an electronic circuit that gives a high output (1) only if all its inputs are high

OR gate

A	B	A+B
0	0	0
0	1	1
1	0	1
1	1	1

The OR gate is an electronic circuit that gives a high output (1) if one or more of its inputs are high.

NOT gate

A
1	0
0	1

The NOT gate is and electronic circuit that produces an inverted version of the input at its output. It is also know as an inverter. If the input variable is A, the inverted output is NOT A.

NAND

A	B
0	0	1
0	1	1
1	0	1
1	1	0

This is a NOT-AND gate which is equal to an AND gate followed by a not gate. The outputs of all NAND gates are high if any of the inputs are low

NOR gate

A	B
0	0	1
0	1	1
1	0	1
1	1	0

This is a NOT-OR gate which is equal to an OR gate followed by a NOT gate. The outputs of all NOR gates are low if any of the inputs are high.

EXOR gate

A	B	A+B
0	0	0
0	1	1
1	0	1
1	1	0

the “Exclusive-OR” gate is a circuit which will give a high output if either, but not both, of its two inputs are high.