SambaNeko... Thank you very much bro. your solution worked! now website visitors can access images only through my scripts (.php & .html pages).

penagate... What u mean exactly... I didn't got it. Thats mean the solution is not practical ... I need a practical solution that works for all visitors of my site. what I want is not avoiding hotlinking. No at all... but I want to protect these images. Only authorized users can see them. Each user is allowed to see a specific image only that related to him. a user can't see other users images. So, I made php script that ask for username & password... if they are correct script will show the image for the user. The URL of the image can be found easily by do right-click -> properties on that image. Thats will lead user to know orther images url... because names are known... I though about making names as combination of random letters and numbers, and store the url for each random string in the database. But still if one of the user know the name of that image... He will be allowed to see them. These images counted as high privacy issue. So I need strongly allow only the one who has the username & password to see only the image he has been allowed to see. I though about storing them into the database. But that will not be practical at all... because of current system specification I dealing with...

If you have an improvment for the solution of our friend SambaNeko... then please share it with us...

Thank you very much for your help