Computers run on binary, that is, ones and zeroes. This counting system utilizes a base of 2. Computers read binary in a way similar to switches, only allowing it to be on or off, true or false. Building with binary is done with stringing together eight digits, or bits to create a byte. A byte is a unit of computer memory. One byte can represent 256 different combinations (two to the power of eight). Two bytes would be two to the power of sixteen, or 65,536 combinations. Bits are the building blocks of bytes and computer speed is dependent on how many bits are read at once. For example, an 8-bit machine means 8 bits are processed at a time.