Represent 83 in 8 bit binary.

Start on the left side of the binary number - the first digit is the "128s" digit - there are no "128s" in 83 (as 128 is clearly larger than 128), so we start with a 0.Next is 64 - there is a 64 in 83, so we have a 1, and have to continue with the remainder: 83 - 64 = 19.Continuing, 32 is larger than 19 so another 0. 16 is smaller, so another 1 and then continue with 19 - 16 = 3.Again, 8 is bigger than 3 - so a 0. 4 is also bigger, another 0. 2 is smaller, so a 1, and then continue with 3-2 = 1. And then one "1s" digit in 1, so a final 1 and we're finished.
Putting it all together, we have 01010011.