What is the purpose of this trick? So reduce lantency? I get that if the browser sends a GET request for a picture, it's possible that the server already answe

What is the purpose of this trick? So reduce lantency? I get that if the browser sends a GET request for a picture, it's possible that the server already answered. But what happens afterwards? Is the connection closed? Or does the server send another JPG again? multipart-mime / content-replace only worked with Netscape, not with IE. What else is needed for this solution? Is there a index.html page with a <img>-tag and some javascript that requests the picture again every time the image was loaded?