The practice of hot linking is when you source an image form a third-party web site, on your own. Meaning, you don't even bother grabbing the image off the third-party web site and placing it on your server, instead, you just call the image, in real-time, off the third-party server.
In many cases, this is normal. For example, I host most of our images shown on this site on Flickr. I pay Flickr a fee to host my images there and I then source the images from them, in real-time, so I don't have to worry about hosting the images and because I like their image service.
But when you source images from a competitors web site, it can get hairy.
A WebmasterWorld thread has one web site owner asking if he should prevent the hot linking from happening or allow it? His rational is that hot linking may help his site be seen as more authoritative in the search engines, and if he allows it, it is a small cost to his overall bandwidth bill. But at this point, he said 20% of his 'visits' come via hot linking and he is concerned it is paying a toll on his server.
Senior member, wheel, said:
My thoughts are that I wouldn't worry about hotlinking until it becomes a load issue.
Of course, if you want to get even with a competitor, you can always use mod_rewrite techniques to serve up a different image to that competitor. So it the image is of a sofa, maybe put a car. If you really want to get them, maybe say, this image is provided by MySite.com, 5% off the price of this site, or something like that.
What would you do?
Forum discussion at WebmasterWorld.