How do AND, OR and NOT gates transform signals?

A logic gate applies a fixed rule to binary signals. Binary means there are two allowed values, written 0 and 1. An ideal gate uses its connected input values to determine one output value; the named operation defines that relationship.

AND has two inputs and produces 1 only when both are 1. If either input is 0, its output is 0. In the illustration, A is 1 and B is 0, so the AND output is 0. One active input is not sufficient for this rule. For example, a rule could allow a process only when both a start request and a permission signal are present. AND expresses that two-condition requirement; it does not decide what the signals mean.

OR is different: it produces 1 when at least one input is 1. The OR used here is inclusive, meaning that two 1 inputs also produce 1. NOT has only one connected input and reverses it, taking 0 to 1 or 1 to 0. A second input is not part of the NOT operation.

A truth table records the output for every allowed input combination, making the rule explicit. The output of one gate can become an input to another, so several small rules can combine into a more elaborate decision. The meaning comes from both the chosen gate and how its signals are connected. A gate's name alone cannot tell the result without its actual inputs.