terabyte

computer science

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Last updated

July 21, 2026

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A terabyte (TB) is a unit of digital information storage. It is equivalent to 1,024 gigabytes (GB) or approximately one trillion bytes. A gigabyte, in turn, is 1,024 megabytes (MB).12

The prefixes used for data storage, such as tera-, peta-, exa-, zetta-, and yottabyte, generally follow the International System of Units (SI), where each prefix represents a power of 1,000. However, in computer science, data is often measured in powers of two. This can lead to discrepancies, where a terabyte drive advertised as 1,000,000,000,000 bytes might actually store 1,099,511,627,776 bytes (1024^4).31

The concept of "big data" refers to extremely large datasets, characterized by volume, velocity, and variety. The amount of data produced globally has grown exponentially, with exabytes and zettabytes becoming common measures.4

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byte
… (GB; one billion bytes) and terabytes (TB; one trillion bytes). Because the byte had its roots in binary digits, originally one kilobyte was not 1,000 bytes but 1,024 bytes (1,024 = 2¹⁰), and thus one megabyte (MB) was 1,024 × 1,024 bytes and so on. However, with some notable exceptions…
Read More
… (GB; one billion bytes) and terabytes (TB; one trillion bytes). Because the byte had its roots in binary digits, originally one kilobyte was not 1,000 bytes but 1,024 bytes (1,024 = 2¹⁰), and thus one megabyte (MB) was 1,024 × 1,024 bytes and so on. However, with some notable exceptions…
Read More