Apple's quest for a next generation operating system

Apple

01/24/1984
01/24/1984 - 10/01/1987
10/01/1987 - 08/01/1996
10/01/1987 - 09/01/1994
09/01/1994 - 03/24/2001
08/01/1996 - 03/24/2001
03/24/2001 - 10/26/2014

Microsoft

08/01/1981 - 11/20/1985
11/20/1985
11/20/1985 - 08/24/1995
07/27/1993 - 02/17/2000
08/24/1995
08/24/1995 - 10/25/2001
10/25/2001
10/25/2001 - 10/26/2014

Personal Computing Era

Approx. 01/08/1981 - 01/21/1984
01/24/1984 - Approx. 08/24/1995
Approx. 08/24/1995 - Approx. 01/01/2015