List of Mac OS versions

System 1.0 - 4.3

 * System 1.0
 * [[System 1.1]
 * System 2.0
 * System 3.0
 * System 3.1
 * System 3.2
 * System 3.3
 * System 4.0
 * System 4.1
 * System 4.2
 * System 4.4

System 6

 * System 6.0
 * System 6.0.1 -- release disputed
 * System 6.0.2
 * System 6.0.3
 * System 6.0.4
 * System 6.0.5
 * System 6.0.7
 * System 6.0.8
 * System 6.0.8L -- never officially released from Apple

Regular Systems

 * System 7
 * System 7.0.1
 * System 7.1
 * System 7.1.1 (System 7 Pro)
 * System 7.1.2
 * System 7.1.2P
 * System 7.1.3
 * System 7.5

Performa Systems

 * System 7.0P1
 * System 7.1P1
 * System 7.1P2
 * System 7.1P3
 * System 7.1P4
 * System 7.1P5
 * System 7.1P6

Mac OS 8

 * Mac OS 8
 * Mac OS 8.1
 * Mac OS 8.5
 * Mac OS 8.5.1
 * Mac OS 8.6

Mac OS 9

 * Mac OS 9
 * Mac OS 9.0.2
 * Mac OS 9.0.3
 * Mac OS 9.0.4
 * Mac OS 9.1
 * Mac OS 9.2
 * Mac OS 9.2.1
 * Mac OS 9.2.2

Mac OS X

 * Mac OS X Public Beta

Mac OS X 10.0 "Cheetah"

 * Mac OS X 10.0.0
 * Mac OS X 10.0.1
 * Mac OS X 10.0.2
 * Mac OS X 10.0.3
 * Mac OS X 10.0.4

Mac OS X 10.1 "Puma"

 * Mac OS X 10.1.0
 * Mac OS X 10.1.1
 * Mac OS X 10.1.2
 * Mac OS X 10.1.3
 * Mac OS X 10.1.4
 * Mac OS X 10.1.5

Mac OS X 10.2 "Jaguar"

 * Mac OS X 10.2.0
 * Mac OS X 10.2.1
 * Mac OS X 10.2.2
 * Mac OS X 10.2.3
 * Mac OS X 10.2.4
 * Mac OS X 10.2.5
 * Mac OS X 10.2.6
 * Mac OS X 10.2.7
 * Mac OS X 10.2.8

Mac OS X 10.3 "Panther"

 * Mac OS X 10.3.0
 * Mac OS X 10.3.1
 * Mac OS X 10.3.2
 * Mac OS X 10.3.3
 * Mac OS X 10.3.4
 * Mac OS X 10.3.5
 * Mac OS X 10.3.6
 * Mac OS X 10.3.7
 * Mac OS X 10.3.8
 * Mac OS X 10.3.9

Mac OS X 10.4 "Tiger"

 * Mac OS X 10.4.0
 * Mac OS X 10.4.1
 * Mac OS X 10.4.2
 * Mac OS X 10.4.3
 * Mac OS X 10.4.4
 * Mac OS X 10.4.5
 * Mac OS X 10.4.6
 * Mac OS X 10.4.7
 * Mac OS X 10.4.8
 * Mac OS X 10.4.9
 * Mac OS X 10.4.10
 * Mac OS X 10.4.11

Mac OS X 10.5 "Leopard"
Siddhu
 * Mac OS X 10.5.0
 * Mac OS X 10.5.1
 * Mac OS X 10.5.2
 * Mac OS X 10.5.3
 * Mac OS X 10.5.4
 * Mac OS X 10.5.5
 * Mac OS X 10.5.6
 * Mac OS X 10.5.7
 * Mac OS X 10.5.8

Mac OS X 10.6 "Snow Leopard"

 * Mac OS X 10.6.0
 * Mac OS X 10.6.1
 * Mac OS X 10.6.2
 * Mac OS X 10.6.3
 * Mac OS X 10.6.4
 * Mac OS X 10.6.5
 * Mac OS X 10.6.6
 * Mac OS X 10.6.7
 * Mac OS X 10.6.8

The features of this version are promising more speed and better memory usage. Friday, August 28 (2009) release.

Mac OS X 10.7 "Lion"

 * Mac OS X 10.7.0
 * Mac OS X 10.7.1
 * Mac OS X 10.7.2
 * Mac OS X 10.7.3
 * Mac OS X 10.7.4
 * Mac OS X 10.7.5

Mac OS X 10.8 "Mountain Lion"

 * Mac OS X 10.8.0
 * Mac OS X 10.8.1
 * Mac OS X 10.8.2
 * Mac OS X 10.8.3

Failed Systems
These system were projected or even worked on before Apple officials applied the brakes; as a result, they never met the light of day.


 * Copland
 * Gerschwin