The byte (B) is the standard unit of digital storage consisting of 8 bits, enough to represent a single character like a letter or number. File sizes, memory capacity, and storage devices are all measured in bytes or their multiples, making it the most commonly referenced unit in computing. One byte equals exactly 8 bits and can represent 256 distinct values.

The kilobyte (KB) equals 1,024 bytes in binary computing terms and is used to measure small files like text documents, email messages, and thumbnail images. While the term sometimes refers to 1,000 bytes in networking contexts, operating systems consistently use the binary definition. One kilobyte can store roughly half a page of plain text.