Definition

1. Noun:
   • A unit of digital information storage: A "megabyte" is a specific measurement used to quantify data in computing and digital systems. It has two common definitions based on different counting systems.

Detailed Meanings

• In binary (base-2) systems: A megabyte (MB) is equal to 1,048,576 bytes, which is 1024 kibibytes or 2^20 bytes. This definition is traditionally used in computer memory and storage contexts.
• In decimal (base-10) systems: A megabyte (MB) is equal to 1,000,000 bytes, which is 1000 kilobytes or 10^6 bytes. This definition is often used by disk drive manufacturers and in some data transfer contexts.

Usage Examples

• Noun:
  • This image file is 2.5 megabytes in size.
  • The software update requires 50 megabytes of free disk space.
  • Older systems often calculated a megabyte as 1,048,576 bytes.

Advanced Usage

• Contextual Ambiguity: The dual definition can lead to confusion. To be precise, the term mebibyte (MiB) is now formally used to denote 1,048,576 bytes, while "megabyte (MB)" is increasingly used to mean 1,000,000 bytes in official standards.
  • For accurate measurement, the specification listed the capacity as 256 MiB (mebibytes), not megabytes.

Variants and Related Words

• Megabit (Mb): A different unit of data equal to one million bits (or 1/8 of a megabyte). Often used in measuring data transfer rates (e.g., internet speed).
  • The download speed is 100 megabits per second.
• Gigabyte (GB): A larger unit of information, typically equal to 1024 megabytes (binary) or 1000 megabytes (decimal).

Synonyms

• MB (common abbreviation).
• Mebibyte (MiB) (specifically for the 1,048,576-byte unit).

Noun

1. a unit of information equal to 1024 kibibytes or 2^20 (1,048,576) bytes
2. a unit of information equal to 1000 kilobytes or 10^6 (1,000,000) bytes