How to create hidden files?

[Dennis Wicks <wix@mgssub.com>]

Greetings;

Back in the dim distant past I remember that one could 
create hidden or "secret" file with Basic on DOS and at 
least early Windows (3.0). I was never able to figure out 
where those files were.

Any way, is there a way of doing this in linux? I know that 
some commands/programs won't show .xx files by default, but 
that isn't the same sort of thing as Basic did.

Any body have an idea?

TIA!
Dennis