2’s complement is a method of representing signed numbers in binary format. In this method, the bits of the number are inverted, and a 1 is added to the end. However, if the number is 0, it is represented as 00000000 in 2’s complement format.

For example, the number 10010 in binary is represented as 11101 in 2’s complement format. The bits are inverted, and a 1 is added to the end. This gives a value of 10100, which is equal to -20 in decimal.

The 2’s complement technique is the most common method of representing signed numbers in binary format. It is simple to implement, efficient in terms of space, and can be used to perform arithmetic operations on signed numbers easily.

Here is an example of how to represent a signed number in 2’s complement format in C:

```
int number = 10010;
// Get the 2's complement of the number.
int two_s_complement = ~number + 1;
```

The `number`

variable is a 8-bit integer. The `two_s_complement`

variable will store the 2’s complement of the number.

The `~`

operator is used to invert the bits of the `number`

variable. The `+`

operator is used to add 1 to the `complement`

variable.

The 2’s complement of the number can then be used to perform arithmetic operations on the number.

Here are some additional details about 2’s complement:

- The 2’s complement of a number is always one greater than the 1’s complement of the number.
- The 2’s complement of 0 is 0.
- The 2’s complement of a negative number is equal to the positive number with the sign bit flipped.