## Register Definition, Types, and Application

A Register is a circuit consisting of Flip-Flops which can store more than one-bit data. The register is nothing but a sequential logic circuit in digital electronics. Before going to know about you must know about the Flip-Flop. So first read about the basics of Flip-Flop.

We know that there are two types of circuits in digital electronics one is Combinational logic circuit and other is Sequential logic circuit. We know that Flip-Flop is a Combinational Logic Circuit.

To store the data in digital form, the concepts of Flip-Flop came. We also know that a Flip-Flop can only store one-bit data. So if we want to store more than one-bit data then what to do? This problem is overcome by making Register.
So Register is nothing but a group of Flip-flops which can store more than one-bit data. In digital electronics Logic Gates, flip-flops, registers are very important and interesting topics because they are the basic components of Microprocessor, CPU, Memory etc.

In this blog, we are always trying to give clear basic knowledge of the topics of electrical and electronics engineering.
To better understand the Register first read the below topics,

### Let's understand Register in detail:

As I told you the Flip-flop is the basic element of the Register so if we want to store four-bit data we need four-bit register. The four-bit register can be made by four flip-flops.

A circuit diagram of a basic 4-bit register is given below,

#### Circuit diagram of Register:

As you see in the above figure the four-bit register consists of four flip-flops. Each flip-flop can store one-bit data. Here D Flip-flops are used. You can also see that the clock terminal of each flip-flop are connected together because we give the clock pulse to all flip-flop together. Always remember that in the case of the register or any memory circuit using flip-flops, the clock pulse is always given together to all the flip-flops.
The concept of Register is very simple and you can understand easily.

Now if I ask you that what is the physical components of a Register? You can give the answer to this question if you have clear basic knowledge about the Register, Flip-Flop, Logic Gate.
But I would say. As we already know that the Registers are made by the combination of Flip-Flops, the Flip-flops are made by the combination of Logic Gates and the Logic gates are made by the combination of Transistors(Most of the cases transistors are used but Diode also may be used).

So the physical components of registers are Transistors or we can say Registers are made by Transistors.

### Examples of Register:

The Accumulator, Stack Pointer, Program Counter in Microprocessor are nothing but a Register.

### Types of Register:

There are mainly two types of the register,
1. General Purpose Register
2. Special Purpose Register
The General purpose registers are mainly stored data. The general purpose registers are,
1. Accumulator
2. Data Register
3. Counter Register
The Special purpose registers mainly to hold the instructions or lines or states of a program before execution. The special purpose registers are,
1. Instruction Register
2. Program Counter

### Application of Register:

1. The main application of register is storing data in digital form.
2. They also can hold data and address
3. The registers are also used to make digital memory chips like ROM Chips, Flash Memory etc.
4. Cache memory in CPU is also made by registers.