How many megabytes are in one gigabyte?

One gigabyte is equal to 1024 megabytes. This relationship is based on the binary system used in computer science, where storage capacities are often expressed in powers of two. In this system, one gigabyte (GB) is defined as (2^{10}) megabytes (MB), which equals 1024. This is an important distinction because while some may think of one gigabyte as 1000 megabytes, that value is derived from the decimal system commonly used in contexts like marketing, rather than the binary calculation used in computing.

The use of 1024 megabytes to define a gigabyte aligns with the practice of using powers of two for memory and data storage, which emphasizes how data and technology fundamentally operate. Thus, the correct answer reflects the established standards within computer science.