Below is a link which, when clicked, will download a .ZIPd file called C-Tutor. It's a tutorial on the C language, but (alas) only runs under DOS ('cause I wrote it sometime during the last century when there was only DOS). However, it works if you have a config.sys file in the C: directory which says:
device=C:\WINDOWS\COMMAND\ansi.sys or device=C:\WINDOWS\DOS\ansi.sys or even device=ansi.sys
(We'll check the config.sys file momentarily.)

Now do the following:

  1. Create a new folder called, say, C-TUTOR (though it can have any name). This folder could be (for example) on your desktop (or anywhere else ... just remember where you put it!)
  2. Download the C-Tutor file (below) to this newly created directory.
  3. You can now get off the internet and close all programs.
  4. Click on the C-Tutor file to unZIP it into your C-TUTOR folder.
  5. Do a Find Files or Folders ... and look for ansi.sys. Make a note of where this file lives, maybe C:\WINDOWS\COMMAND\ or maybe C:\WINDOWS\DOS\ or maybe just C:\. You'll have to tell config.sys, next.
  6. Do a Find Files or Folders ... and look for config.sys.
  7. Open config.sys with Notepad and make sure it contains a device = ... ansi.sys line (one of the above-mentioned lines, such as device=C:\WINDOWS\COMMAND\ansi.sys
    If it already has such a line you're in luck. No need to add such a line. If not, add such a line.
  8. Save the config.sys file and close all programs.
  9. Restart your PC in MS-DOS MODE *. The screen will probably say something like:
    C:\WINDOWS\
  10. Get yourself into the C:\WINDOWS\DESKTOP\C-TUTOR directory (or wherever you saved the C-Tutor file and its unZIP'd comrades) by typing:
    C:\WINDOWS\DESKTOP\C-TUTOR
    (or equivalent ... depending upon the name you gave your folder)
  11. Type dir and you'll see the collection of unZIP'd files, like:
display, contents, explain, lesson1 to lesson12, and a couple of tests.

The magic program, here, is the one called display 'cause it ... uh, displays things.

Type:
display explain
... and the display program will be explained.
Type:
display lesson1
... and the first lesson in C will be displayed.
Type:
display test1-5
... and a test on lessons 1 to 5 will be displayed.

* Instead of restarting your PC in DOS MODE, you may be able to simply open a DOS window. See if you can find an MS-DOS PROMPT (under Programs maybe?) to get into DOS and, to get a smaller DOS window, try Alt Enter. When you get a window, then get into the appropriate directory (as per step 10, above), and get something like this (after typing display lesson1):

Okay, if you're still game to try it, click here:

Download C-Tutor

One last thingy: although I wrote these lessons, it was when I was an infant.
Now, a decrepit old man, I can't remember a thing about this $!#&%@? language ... so don't ask me any questions!