Hello World and the story behind

I have a better reason for the above title than the fact that this is indeed my first posting on this blog. I was trying to get my makefile(s) that were developed for Windows (nmake) to work under Linux. When I tried to link all the objects compiled using gcc (using -c option) I was faced with the following error.

ld: warning: cannot find entry symbol _start; defaulting to 0x0804844c

The first hit on Google was this very interesting teaching material by a professor in a Brazilian University that reveals the hidden behind the scenes of the Hello World saga. (http://www.lisha.ufsc.br/~guto/teaching/os/exercise/hello.html). Check it out ...