Hot linking or remote linking is when someone embeds an image or any file directly onto their website instead of downloading it into their hard drive and sourcing it from there.
For example: Someone likes and image on your website, and wants that image for their website. If you they use the full URL of your image on their site, then the image is downloading from your site every time someone looks at their website. In effect they are using your bandwidth for the image.
Why hot linking is bad for you
You might think others linking the images or files on your site is cool and will be good for exposure, but what they are doing is actually nothing short of bandwidth theft. Hot linking will also increase your bandwidth, and when you exceed your bandwidth webhosts will take action. They will just lower your speed if you are lucky, they might also choose to shut you down.
When you enable Hot Link Protection, no one can steal your bandwidth anymore.
To enable or disable hot link protection, just do the following:
Your images are now being protected from being hot linked. Now all you have to do is make sure that all of your additional domains are in the Hot Link list.
Note: There is a chance that your images may stop working. When this happens you have to check your HTML source code for a common problem. Some website designers or even programs may decide to use absolute path names for your images. So instead of a relative path like “/images/pic.jpg”, it might be using an entirely different URL.
You must have that correct protocol and domain name listed in the “URLs to allow access”. Any mistake or slight difference in the protocol or in the domain name between the allowed list and the HTML source code will cause your images to be blocked.
Another reminder: Some firewalls (like those such as Symantec’s Norton Internet Security and ZoneAlarm) are programmed to block a special referrer variable to provide more privacy to the user. Hotlink protection is designed to work with this variable and tell you where the request is coming from.
Learning how to hotlink will go a long way to protecting your bandwidth. However, it is also recommended that you use hot link protection with a degree or reservation. Hot link protection may protect against bandwidth theft, but it does have a disadvantage; it will eventually block legitimate requests from visitors using one of those firewalls. This is why it is advisable to have the option to “Allow direct requests”.