What is the difference between <pc-name> and <pc-name>.<domain-name>?

Hi,

Can anyone give advice? I am not familiar with networking stuff.

Currently I am having problem with the url of website…
If url name is just using (e.g. http:///test/default.aspx), the links in web page will work perfectly fine. But, if url name is using .(e.g. http://./test/default.aspx), some of the links which need javascript functions are not working.
But, if the scenario above is tested on other pc, it works perfectly fine. If the scenario above is tested on the pc itself(i.e. the pc whose name is ), it will have the error mentioned above.

Really appreciate if anyone can give advice on this. Thanks in advanced!

Rgds,
Grace83f