The term "giga" is a prefix in the metric system that denotes a factor of one billion, or 10^9. It is commonly used in various fields, such as computing and telecommunications, to describe large quantities. For example, a gigabyte (GB) is a unit of digital information storage equal to one billion bytes. In addition to computing, "giga" is also used in scientific contexts, such as measuring distances in astronomy. For instance, a gigameter is one billion meters, which can be useful when discussing vast distances in space.