In the above example, the result is an 8-bit number, as it can be stored in the 8-bit computer, so we get the correct results.

In the above example, the result is a 9-bit number, but we can store only 8 bits, and the most significant bit (MSB) cannot be stored.

The result of this addition will be stored as (00101011) which is 43 and it is not the desired result. Since we cannot store the complete result of an operation, and it is known as the overflow case.

The smallest unit of information is known as BIT (BInary digit).

The binary number 110011 consists of 6 bits and it represents:
                                  

For an n-bit number the coefficient is -     multiplied by     where,  ( )