Desktop Evolution.

Here is a wonderful collection of the most influential desktops. If you are looking for further info, then don't forget to check out this link, here Wikipedia has a very nice article on this history of the GUI.

1984 - 1986
January 1984: Macintosh System 1.

April 1985: Macintosh System 2.

November 1985: Microsoft Windows 1.0.

November 1985: Microsoft Windows 1.0.

January 1986: Macintosh System 3.

1987 - 1989
March 1987: Macintosh System 4.

1987: Macintosh System 5.

December 1987: Microsoft Windows 2.0.

December 1987: Microsoft Windows 2.0.

April 1988: Macintosh System 6.

1990 - 1994
May 1990: Microsoft Windows 3.0.

May 1991: Macintosh System 7.

August 1992: Microsoft Windows 3.1.

August 1992: Macintosh System 7.1.

1995 - 1997
March 1995: Macintosh System 7.5.

August 1995: Microsoft Windows 95.

July 1997: Mac OS 8.

1998 - 1999
June 1998: Microsoft Windows 98.

July 1998: KDE 1.0.

October 1999: Macintosh System 9.

2000 - 2001
October 2000: KDE 2.0.

September 2001: Mac OS X 10.1.

October 2001: Microsoft Windows XP.

2002 - 2007
November 2005: KDE 3.5.

Mac OS X 10.5.

Microsoft Windows Vista.

Source

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