1. University of Utah 1 “Free software” Remember... In the beginning, all software was free -Just a means to sell hardware

2. University of Utah 2 Public Domain Something that is not copyrighted -Anyone can use or modify it without restrictions Most early software was in this category

3. University of Utah 3 Public Domain Very popular in minicomputer / microcomputer era -BASIC Examples

4. University of Utah 4 Potential Problem Public domain software can be -modified -resold as commercial software

5. University of Utah 5 Potential Problem Public domain software can be -modified -resold as commercial software Example: -UNIX

6. University of Utah 6 Potential Problem Public domain software can be -modified -resold as commercial software Example: -UNIX -BASIC (depends on your point of view)

7. University of Utah 7 Richard Stallman Programmer at MIT’s AI lab (1970s) Disillusioned by increasing commercialism in software http://vududevil.wordpress.com/2007/11/06/richard-stallman-llena-teatro-en-tijuana-bc/

8. University of Utah 8 Richard Stallman Founds GNU project (1983) -“Gnu’s Not Unix” Goal: -Create a “free” implementation of Unix

9. University of Utah 9 Free? As in “free pizza”? -No.

10. University of Utah 10 10 Free? As in “free pizza”? -No. As in “freedom”? -It depends on who you ask.

11. University of Utah 11 11 Free? As in “whatever Richard Stallman’s definition of freedom is?” -Yes!

12. University of Utah 12 12 GPL GNU General Public License In a nutshell: -You must have access to source code -You can modify the software at will -If you distribute it, you must provide access to source code grant same rights to modify & distribute

13. University of Utah 13 13 Gradual success... Text editor: Emacs Compiler: GCC Parser generator: Bison Other utilities slowly coalesce

14. University of Utah 14 14 Gradual success... Almost a completely functioning OS (1990) Missing one piece... -The “kernel”

15. University of Utah 15 15 Meanwhile....

16. University of Utah 16 16 Linus Torvalds 1991 22-year-old student at University of Helsinki (Finland) Wrote a terminal emulator for MINIX http://www.linuxtoday.com/special/lwce2/big_linus_keynote.jpg

17. University of Utah 17 17 Linux Terminal emulator project evolves into an operating system -Version 0.01 -17 September 1991

18. University of Utah 18 18 Linux Original name: “Freax” A friend suggested “Linux” instead

19. University of Utah 19 19 Copyright Original copyright said Linux could not be sold -Problematic So, Linus switched to GPL for version 0.12 -Why?

20. University of Utah 20 20 And now... Suddenly -GNU project had a kernel! -A complete Unix-compatible system without Unix.

21. University of Utah 21 21 And now... Suddenly -GNU project had a kernel! -A complete Unix-compatible system without Unix. -(well, almost.)

22. University of Utah 22 22 Progress Version 0.12 supports X Window System (1992) Next version: 0.95 (1992) Version 1.0 (1994)

23. University of Utah 23 23 Idealogy clashes Linus Torvalds vs Andrew Tanenbaum

24. University of Utah 24 24 Idealogy clashes Linus Torvalds vs Andrew Tanenbaum Richard Stallman vs the world

25. University of Utah 25 25 Idealogy clashes Linus Torvalds vs Andrew Tanenbaum Richard Stallman vs everybody “Open source” vs “Free software”

26. University of Utah 26 26 Reminder Presentation sign-ups

27. University of Utah 27 27 “Test Question” On a scrap of paper, write a question that encapsulates one of the points from today's class, and turn it in. (Put your name on it!)