BBA GCSE Computing

What is binary?

The Number system we use every day is called Base 10 or denary, because you multiply by 10 each time (1*10=10, 10*10=100) however, the number system that computers use is called base 2 or binary. 1 means on and 0 means off. Those are the only numbers that are represented in binary. Going along from right to left on 8 bit binary (a byte): 1 is the first slot, 2 is the second, 4 is the third, 8 is the fourth, 16 is the fifth, 32 is the sixth, 64 is the seventh, and 128 is the eighth.

Binary to denary and vice versa!

How to convert from binary to denary and vice versa!

Converting Binary to denary!

10000001 is an eight bit (byte) binary number. The first slot on the left, as stated above is 128.

You only count the numbers which have the number 1 in their slot. The first one on the right is 1. Whichever place is on, you add up the corresponding numbers! This one is 129.

Converting denary to binary!

You take a number, say, 35 and you try to make it with binary. You cannot use 128 and 64, but you can use 32. So 35-32=3. We now need to make 3. We cannot use 16, 8 or 4, but you can use 1 and 2! So the binary number will be.... Drum roll please! .......... 00100011!
Thanks for reading!