If you don't get the title, you're probably too young to get the rest of this. If you don't know who John Backus was or what his contribution to computer science was then you're also, probably, too young.

The first programming I ever did was in a language called DITRAN using punched cards. DITRAN was a Diagnostic version of FORTRAN. I found it about as interesting as watching the corn grow.

Some years later, sitting in front of a CRT, it was a completely different story, I was hooked. We were developing accounting applications in FORTRAN 66 (you read that right) on a Prime 300 mini-computer. Prime had a BASIC interpreter, but that was for wimps.

So, today I wondered if I could compile and run a FORTRAN program on Linux. First problem I had, was I couldn't remember enough FORTRAN to actually write a program, so I stole this from the Wikipedia FORTRAN page. Had to make a few slight modifications to get it to compile:

C AREA OF A TRIANGLE WITH A STANDARD SQUARE ROOT FUNCTION 
C INPUT - CARD READER UNIT 5, INTEGER INPUT
C OUTPUT - LINE PRINTER UNIT 6, REAL OUTPUT
C INPUT ERROR DISPLAY ERROR OUTPUT CODE 1 IN JOB CONTROL LISTING
      READ 501, IA, IB, IC
  501 FORMAT (3I5)
C IA, IB, AND IC MAY NOT BE NEGATIVE
C FURTHERMORE, THE SUM OF TWO SIDES OF A TRIANGLE
C IS GREATER THAN THE THIRD SIDE, SO WE CHECK FOR THAT, TOO
      IF (IA) 777, 777, 701
  701 IF (IB) 777, 777, 702
  702 IF (IC) 777, 777, 703
  703 IF (IA+IB-IC) 777,777,704
  704 IF (IA+IC-IB) 777,777,705
  705 IF (IB+IC-IA) 777,777,799
  777 STOP 1
C USING HERON'S FORMULA WE CALCULATE THE
C AREA OF THE TRIANGLE
  799 S = FLOAT (IA + IB + IC) / 2.0
      AREA = SQRT( S * (S - FLOAT(IA)) * (S - FLOAT(IB)) *
     +     (S - FLOAT(IC)))
      WRITE (0,601) IA, IB, IC, AREA
  601 FORMAT (4H A= ,I5,5H  B= ,I5,5H  C= ,I5,8H  AREA= ,F10.2, 
     +        13H SQUARE UNITS)
      STOP
      END
To compile it you'll need the gcc-fortran package for your distro. Assuming the source file is "test.f" compile it with the following command:
  $ gfortran test.f
Running it is simple, although it took me a while to remember that FORTRAN likes its input values separated by commas:
  $ ./a.out
  3,4,5
  A=     3  B=     4  C=     5  AREA=       6.00 SQUARE UNITS
Also took me a while to figure out some acceptable input values... can you say trigonometry?.

If none of this is new to you, if it seems quite old-hat, then maybe you're involved in some sort of HPC (High Performance Computing). If so, check this link and maybe you can pass along some of that knowledge to some of these youngsters.