Apple's history and milestones

Here are some of Apple's milestones:

1976 - High-school buddies Steven Wozniak and Steve Jobs start Apple Computer. Their first product, Apple I, built in circuit board form, debuts at "the Homebrew Computer Club" in Palo Alto, California.

1977 - Apple II is unveiled, the first personal computer in a plastic case with color graphics.

1983 - Apple starts selling the "Lisa," a desktop computer for businesses with a graphical user interface, the system most users are familiar with today.

1984 - Apple debuts the Macintosh personal computer.

1985 - Jobs leaves Apple after a power struggle.

September 1997 - Jobs is named Apple's interim CEO after the company records losses of more than $1.8 billion.

November 1997 - Jobs introduces a new line of Macintosh computers called G3, and a website that lets people order directly from Apple.

1998 - Apple unveils the iMac desktop computer.

2001 - Apple introduces the iPod.

2003 - The iTunes Store opens, allowing users to buy and download music, audiobooks, movies and TV shows online.

August 2004 - Jobs announces he underwent successful surgery to remove a cancerous tumor from his pancreas.

January 2007 - Apple introduces the iPhone.

2008 - Apple opens its App Store as an update to iTunes.

January 2009 - Jobs takes leave for health reasons. COO Cook leads the company in the interim.

June 2009 - Jobs returns to the company after undergoing a liver transplant.

April 2010 - Apple begins selling the iPad, a 10-inch touchscreen tablet, and has an 84 percent share of the tablet market by year's end.

Jan. 17, 2011 - Jobs announces that he will take another medical leave.

March 2, 2011 - Apple launches the iPad 2.

Aug. 9, 2011 - Apple briefly edges past Exxon Mobil Corp to become the most valuable U.S. company.

Aug. 24, 2011 - Jobs steps down as CEO and is replaced by Tim Cook, Apple's chief operating officer.

Oct. 5, 2011 - Jobs dies at age of 56 after battle with pancreatic cancer.