What is the crossword answer for the clue: Windows alternative

DOS - a 3 letter word may be the answer you are looking for!

UNIX - a 4 letter word may be the answer you are looking for!

LINUX - a 5 letter word may be the answer you are looking for!

OSX - a 3 letter word may be the answer you are looking for!

Windows alternative

3 Character Answers:

DOS

OSX

4 Character Answers:

UNIX

5 Character Answers:

LINUX