.htaccess?

For a schoolproject, I have to set up an intranet at a company headquarters in the Netherlands. But they want to give the division in the United States access to that intranet.

I have to find out how to do that. I've heard that you can do that by giving certain people access to the intranet with a .htaccess file.

Can somebody tell me how I can use the file for this? Is there an official specification for the .htaccess file?

the specs are a part of apache. www.apache.org