The document outlines major milestones in the development of hard disk drive (HDD) technology from 1956 to 2009. Some of the early milestones included the introduction of the first HDD by IBM in 1956 and Memorex shipping the first IBM-compatible third party HDD in 1968. HDDs continued to improve through the 1970s and 1980s, becoming standard on PCs. Capacities grew significantly, reaching 170 MB and 340 MB with IBM's micro hard drive release in 1999 and breaking the 137 GB addressing barrier in 2002. Form factors also shrank as demonstrated by IBM's 0.85 inch 2 GB drive in 2004 and the first 200 GB 2.5 inch drive in 2006.