The 
Space Quest series of 6 games describes the adventures of heroic (if clumsy and none-too-bright) janitor 
Roger Wilco as he campaigns through the galaxy for truth, justice and really clean floors.  
Initially created for 
Sierra by the famous 
Two Guys from Andromeda (who made a guest appearance in SQ3), the games were mainly a vehicle for terrible puns and really silly puzzles, as Roger fights the likes of Sludge Vohaul and the Pirates of Pestulon to save the galaxy and impress girls. 
 
Unlike the 
LucasArts games, miscalculations and bad choices can lead to the unfortunate (but generally hilarious) demise of your hero - followed by the dreaded "Restore/Restart" screen.  
You DID save your game, didn't you?
-  SQ 1 - Sarien Encounter (Original Text Input)	1986
-  SQ 1 - Sarien Encounter (New Icon-Parser)	1990
-  SQ 2 - Vohaul's Revenge			1987
-  SQ 3 - The Pirates of Pestulon		1989
-  SQ 4 - Roger Wilco and the Time Rippers	1991
-  SQ 5 - The Next Mutation      		1993
-  SQ 6 - The Spinal Frontier
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