A byte is a piece of data composed of eight binary digits. A binary digit is simply a one or a zero, and is used to communicate with computers. Bytes are typically represented in hexadecimal (denoted by a ‘0x’ at the beginning) rather than binary (denoted by a ‘0b’ at the beginning) for readability. In Bitcoin, transactions, scripts, public keys, and blocks are all series of bytes represented in hexadecimal format.