A logic gate is an electronic circuit that controls the flow of electron according to logic. It implements Boolean function and in most cases produces one output from one or more binary inputs. In logic gate, logical operations are carried out by electrical switching circuits. At any moments, it follows the rules of logic where every terminal of the circuit is in one of the two binary conditions false or true. Here false represents 0 (NO) and true represents 1 (YES).

Logic gates are commonly used in devices like microprocessors, multiplexers, demultiplexers, encoders, decoders, registers, adders, etc. One microprocessor may contain more than 100 million gates. In this case, millions of logic gates are packaged in a single integrated circuit (IC).

## Types of logic gate:

**Basic logic gate:** The logic gate which can perform its logical function without the help of any other logic gate is called Basic logic gate. AND, OR and NOT gate are the Basic logic gates .

**Universal logic gate:** The NAND and NOR gates are universal gates. In practice, this gate can implement any Boolean function without need to use any other gate. These gates are comparatively economical and easier to formulate.

**Exclusive gate:** An exclusive OR gate is a digital logic gate that performs exclusive disjunction operation with two or more inputs and produces one output. XOR and XNOR gate are the example of Exclusive gate.

**Compound or complex logic gate:** Compound or sometimes called complex logic gates are gates that can function like other few logic gate in combined.

## Symbol of Logic gate :

There are two sets of symbols for elementary logic gates. They are “distinctive shape” and “rectangular shape”. Both are defined in ANSI/IEEE Std 91-1984. The “distinctive shape” is based on traditional schematics, is used for simple drawings. The “rectangular shape” set is based on ANSI Y32.14.

## Application of Logic gate:

A Logic gate is a building block of digital electronics. Almost all electronic devices like computers, tablets, smart phones, calculators, washing machines, lifts etc are made using logic gates. Logic gates are used to make combinational circuits such as multiplexers, demultiplexers, encoders, decoders, etc. Logic gates include such devices as registers, arithmetic logic units (ALUs), and computer memory. Millions of tiny logic gates are combined to produce an integrated circuit (IC)

## Importance of Logic gate:

Logic gates implement Boolean function and generate one output from one or more inputs. All the electronics are based on logic gates. If we consider a computer as an electronic device, it is made by using many chips. Microprocessor is a small chip inside the computer. Microprocessor consists of small components: control unit, register, ALU and inputs and output ports. Here each component of the microprocessor has its respective function. Ultimately, all the components are only the combination of logic gates. In our daily affairs, we closely go to a number of electronic devices to find the solution of our problems. These devices are produced using logic gate. So, we can say logic gate helps us to solve our problems, to make decision and to generate new ideas to go ahead. Living in this digital world, we cannot deny logic gate.