8.logic gates

Component	Symbol	definition
AND		An AND gate can have two or more inputs. The output of an AND gate is true when all its inputs are true.
OR		An OR gate can have two or more inputs. The output of an OR gate is true when at least one of its inputs is true.
NOT		A NOT gate can only have one input. A NOT gate is also called an inverter.
NAND		A NAND gate can have two or more inputs. The 'o' on the output means 'not' showing that it is a Not AND gate. The output of a NAND gate is true unless all its inputs are true.
NOR		A NOR gate can have two or more inputs. The 'o' on the output means 'not' showing that it is a Not OR gate. The output of a NOR gate is true when none of its inputs are true.
EX-OR		An EX-OR gate can only have two inputs. The output of an EX-OR gate is true when its inputs are different (one true, one false).
EX-NOR		An EX-NOR gate can only have two inputs. The 'o' on the output means 'not' showing that it is a Not EX-OR gate. The output of an EX-NOR gate is true.