Seagate has announced the shipment of its billionth hard drive, and said that it aims to sell another billion in the next five years.

The company (then Shugart Technology) shipped its first drive in 1979, the 5MB ST506 which was the first 5.25in drive and cost $1,500.

Seagate estimates that it has shipped 79 million terabytes of storage in its 29-year history.

"Digital content proliferation is a long-term phenomenon," said John Rydning, research director for hard drives at IDC.

"This phenomenon is pushing demand for hard drives to more than 600 million units a year by 2010, and will continue to fuel demand in the decade ahead."

As volumes have risen in the industry so prices have fallen. The first Seagate drives cost $300 per megabyte, compared to one fiftieth of a cent today.

Bill Watkins, chief executive at Seagate, said: "Al Shugart and a few others started the company behind a convenience store in 1979 and enabled the birth of the first PCs."