logic gates

¿What is a logic gate?

Logical gates are electronic circuits capable of performing basic logic operations. For example, to perform the product operation, we can use an integrated circuit from which the result S = A · B is obtained

 In the next image we can see the types of logic gates that exist whit  the respective tru table.

AND

The output signal is activated only when all the input signals are activated.  Equivalent to the logical product S = A · B

OR

The output signal is activated if any of the input signals A or B

 NOT

The output signal is activated when the input signal is turned off.  It is the inverse.
Equivalent to denial or inversion S = A '

NAND

The output signal is activated as long as all the input signals are not activated.  It is equivalent to combining an AND and a NOT gate.  Equivalent to the inverse of the logical product S = (AB) 'and corresponds to the  following table of truth and the following electric circuit:

The output signal is activated as long as all the input signals are not activated. The  NAND gate is represented by these two symbols (the one on the left is normalized).  It is one of the easiest puerta to find and most commonly used: