Considerations

Besides these, many other concepts that must be clearly distinguised : freeware, public domain, shareware, shared source, etc.

Free vs. no cost... after all, it always costs

OpenSource vs. open / shared, ... who controls what ?

Freeware,

Shareware,

...

Don't believe what vendors claim.

What is the real importance of the "software industry" : Software off-the-shelf / shrink-wrap vs. custom made.