Software & Freedom

Lonce Wyse

Communication & New Media

lonce.wyse@cnm.nus.sg

Operating System 

Operating System 

DOS

Unix

Linux

Android

iOS

http://en.wikipedia.org/wiki/Operating_system

Licenses

• Preserve Copyright

• Preserve ownership

• Give specific rights

Popular Licenses

• GNU GPL
  • Gnu General Public License
  • Use, Study, Copy, Modify, Share
    •  as long as license & source code is provided
    •  new code is GPL
• LGPL
  • "Lesser" GPL
  • Can combine with proprietary software
• MIT & BSD
  •  "permissive"
  • Not "copyleft" because derivatives don't require the same license
  • "as is"