A unit consisting of a number of flip-flops that work together as a unit and can hold a binary word is called a register. The memory of a computer is made up of registers. Types of registers:
Based on the data input and output, they can be divided into four categories:
1.Parallel In Parallel Out (PIPO)
2. Parallel In Serial Out (PISO)
3. Serial in Serial Out (SISO)
4. Serial In Parallel Out (SIPO)
Shifting can be divided into three categories based on:
1.Left Shit Register
2. Right Shift Register
3. Rotated Shift Register
Based on controlling, it can be divided into two categories:
1.Un- Controlled
2. Controlled