1. University of Utah 1 IBM Dominates the industry Critics complain that IBM doesn't innovate -Sound familiar?

2. University of Utah 2 IBM 7090 / 7094 Transistorized version of IBM 709 The “classic” mainframe!

3. University of Utah 3 IBM 7094 150 K memory 36-bit word length As fast as a PC in 1980's

4. University of Utah 4 Backwards compatibility IBM's golden handcuffs... 704 → 709 → 7090 → 7094

5. University of Utah 5 Smaller machines IBM 1401 (1959) >10,000 installed! Sometimes used as a peripheral for larger computers

6. University of Utah 6 Disk Drives First suggested by Eckert (1940's) Engineered by IBM (1956)

7. University of Utah 7 Disk Drives IBM RAMAC -“Random Access Memory Accounting Machine” -50 aluminum disks -24 inch diameter -1200 rpm -5 million characters

8. University of Utah 8 Mainframe Era Never left idle! Not interactive -programmers did not use the machine directly Data available as printouts

9. University of Utah 9 Software Didn't exist as we know it at first -ENIAC's cables and dials -Machine language

10. University of Utah 10 10 Early tools Separate machine for programming -Harvard Mark III -Zuse “Plan Preparation Machine”

11. University of Utah 11 11 Breakthrough #1 Use the computer as its own “plan preparation machine!”

12. University of Utah 12 12 Breakthrough #2 Reuse previously-written routines Origin of term “compiler”

13. University of Utah 13 13 Grace Hopper First “modern” programmer -Harvard Mark III calculator -UNIVAC

14. University of Utah 14 14 Precursors Whirlwind computer's “Translation program” -Similar to modern compilers -Not general purpose -Slow

15. University of Utah 15 15 Precursors Assembly language -Each “keyword” corresponds to a single machine language instruction -Popular until 1980s/1990s

16. University of Utah 16 16 Users Groups SHARE -“Society to Help Avoid Redundant Effort” -IBM 701/704 users -Shared code routines for common problems

17. University of Utah 17 17 Sorting “Files” on magnetic tape Sorted alphabetically/numerically What happens if you change (or add or delete) a file?

18. University of Utah 18 18 Sorting Not just an academic exercise -Matter of business survival! UNIVAC's first software was a tape- sorting routine -Written by Betty Holberton

19. University of Utah 19 19 FORTRAN “Formula Translation” Designed for IBM 704 (1957) Syntax similar to algebra Machine-specific commands

20. University of Utah 20 20 FORTRAN Many revisions -FORTRAN II, III, IV -FORTRAN 66, 77, 90 -FORTRAN 95, 2003, 2008

21. University of Utah 21 21 FORTRAN Still used today! -Supercomputers -Benchmarks

22. University of Utah 22 22 COBOL Common Business Oriented Language (1960) Inspired by Grace Hopper's compilers for UNIVAC Cross-platform by design

23. University of Utah 23 23 COBOL “Self documenting” verbose code C: if (employeeHours > maximum) COBOL: IF EMPLOYEE-HOURS IS GREATER THAN MAXIMUM

24. University of Utah 24 24 COBOL There's more than one way to do it! COMPUTE X = (-B + (B ** 2 - (4 * A * C)) **.5) / (2 * A) MULTIPLY B BY B GIVING B-SQUARED. MULTIPLY 4 BY A GIVING FOUR-A. MULTIPLY FOUR-A BY C GIVING FOUR-A-C. SUBTRACT FOUR-A-C FROM B-SQUARED GIVING RESULT-1. COMPUTE RESULT-2 = RESULT-1 **.5. SUBTRACT B FROM RESULT-2 GIVING NUMERATOR. MULTIPLY 2 BY A GIVING DENOMINATOR. DIVIDE NUMERATOR BY DENOMINATOR GIVING X.

25. University of Utah 25 25 “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!)