2s Complement

Two’s Complement is required for representing signed integers. If the high bit is 1 (i.e. if the binary number is 128 or greater in an 8-bit system), then the number is negative. To find the negative value, invert all bits and add 1.

Example:

To convert the binary number 11111010 to decimal:

First, invert all the bits: 00000101

Then, add 1: 00000101 + 1 = 00000110

Finally, convert to decimal: 6