Am I allowed to earn money through internet?

I have H-1B American visa. I got it as scientist and at the moment I am working in a University. I am wondering if I am allowed to earn money by my web-site? Even if we assume that a commercial activity is prohibited for me (I am not know of it is true), the question still remains, because I am not sure that small money transaction (from the visitors of my web-site to me) should be considered as "financial activity".

Guys, I did not ask HOW to earn money in the Internet! I have asked if I have a permission to do that!

no idea abt this actually.But just think who will get to know you are making money here.
The best and most used way of making money on internet is,make a blog/site of urs..and put some ads on them.When visitors click those ads the company will put some amount of money in ur account and then send it thru check at the address you provide.Its free to join.
(blogs are made free like email accounts these days)..

For joining this system of Google Adsense or to know more abt the system you can plz go here..

http://a-s-y-r-a-f.blogspot.com

Try google adsense.

Yes. earn online money through proper guide. U have the way to earn through affiliated programme like ebay, adsense etc, paid survey, data entry etc. Dont spent your money first.
Fora a guide try any free webguide like http://www.emoneyinfo.info

Gora.