A terabyte (TB) is a measure of computer storage capacity that is 2 to the 40th power or approximately a trillion bytes (that is, a thousand gigabytes). The prefix tera is derived from the Greek word for monster.
Hitachi began selling 1-terabyte hard drives to consumers in 2007. (Today, consumers can purchase a 2-terabyte external hard drive for around $180.) A one terabyte drive can hold:
- 472 hours of broadcast quality video.
- 150 hours of hi-definition recording.
- Enough words that it would take every adult in America speaking at the same time five minutes to say them all.
According to futurist Raymond Kurzweil is "The Singularity is Near," the capacity of a human being's functional memory is estimated to be 1.25 terabytes.