A yottabyte is a unit of digital information storage that equals one septillion bytes, or 1,000,000,000,000,000,000,000,000 bytes. It is part of the International System of Units (SI) and is denoted by the symbol Y. Yottabytes are used to measure vast amounts of data, often in contexts like cloud storage, big data, and data centers. To put it in perspective, a yottabyte could store approximately 250 trillion DVDs worth of data. This immense capacity is beyond what most individuals or even large organizations typically require, making it a concept more relevant to large-scale data management and analysis, such as in artificial intelligence and scientific research.