The term "mega" is a prefix used in the metric system to denote a factor of one million (10^6). It is commonly used in various fields, such as science and technology, to describe large quantities. For example, a megabyte is a unit of digital information equal to one million bytes. In everyday language, "mega" can also be used informally to mean something very large or impressive. For instance, someone might describe a mega sale as a huge discount event, or a mega concert as a large music event featuring popular artists.