Key dates in the history of Apple, whose ailing co-founder Steve Jobs resigned as CEO this week.

1976: Steve Jobs and Steve Wozniak unveil the first Apple computer in Palo Alto, California. It consists of little more than a circuit board and costs just under $700.

1977: The Apple II with a one-megahertz processor becomes the first mass produced computer and an instant hit.

1980: Apple becomes a publicly traded company.

1983: Lisa, the first personal computer featuring a mouse for navigating and desktop icons and folders, is introduced. Its failure is blamed on a daunting price of nearly $10,000.

1984: The Macintosh PC makes its debut. It is affordable and features innovations such as a disk drive, built-in monitor, and a mouse.

1985: Mr Jobs resigns after being stripped of control of Apple in an internal power struggle.

1986: John Sculley becomes Apple president. Steve Jobs starts computer company NeXT and buys Lucasfilm's computer graphics division, renaming it Pixar.

1996: Apple buys NeXT and makes Steve Jobs an adviser.

1997: Mr Jobs returns as head of Apple. Arch-rival Microsoft invests $150m in the company.

1998: Steve Jobs revamps Apple's product line, churning out colourful $1,300 iMac PCs with monitors and drives in the same casing.

1999: The iBook, marketed as a mobile iMac, is introduced.

2001: Apple launches the iPod pocket digital music player for $399 and opens its first retail store in Palo Alto.

2003: Apple opens online music store iTunes.

2004: Jobs undergoes an operation for pancreatic cancer.

2007: Apple kicks off the era of the touchscreen smartphone with the new iPhone.

2009: Jobs goes on medical leave in January, returning to work in June after undergoing a liver transplant.

2010: Jobs unveils the iPad tablet computer, a huge hit after it goes on sale in April. Apple passes Microsoft in May as the largest US technology company in terms of market value.

2011: 17 January: Jobs takes another medical leave of absence.

18 January: Apple reports a record quarterly net profit of $6bn on revenue of $26.74bn.

2 March: Jobs makes a surprise appearance to unveil the latest iPad.

6 June: Jobs again surprises by launching Apple's free online storage hub iCloud.

19 July: Apple second quarter profit hits $7.31bn on revenue of $28.57bn.

9 August: Apple briefly passes ExxonMobil as the world's largest company by market capitalisation.

24 August: Jobs announces his resignation as CEO and is replaced by chief operating officer Tim Cook, but stays on as chairman of the Apple board.