Computers use binary numbers because they have circuits which are either on or off, which gives them two states to work from to make calculations and run processes. The two-digit, or base 2, number system is much easier for the computer to process with the circuits they have. The binary numbers have values for each space in a number, just like regular numbers with the ones, tens and hundreds places.
In binary numbers, instead of each number place being multiplied by ten, they are multiplied by two. This allows long strings of number to still be translated into standard numbers and letters. Eight binary number strings are the most useful and most used set of binary numbers. The eight-number sets allow the computer to process numbers from zero to 255. These eight numbers are also the smallest binary sets that give the right amount of number options to represent letters. This is similar to how the binary numbers are used to represent pictures. Pictures are made up of pixels, which are digital representations of the picture. The pixels coincide with binary codes, which tell the computer how much red, blue or green is needed to create the color on the screen. Each pixel is normally represented by up to three bytes, or three of the eight digit binary codes.