Highlights:
Film tends to retain highlights without blowing them out or overexposing them. For instance, if you’re shooting with a very bright area within your frame such as a bright sky, you run the risk of overexposing the sky in order to get the correct exposure on your relatively dark subjects (especially if you are shooting your subjects backlit). If your highlights are overexposed, then they look completely white with no color information at all in that area. Many people don’t mind this look (myself included) but it’s technically a photography no-no.
Why is film better at the highlights? With film, exposure is all about a physical process of the film reacting to light coming into the camera. It’s actually a more common problem for film to be underexposed than to be overexposed. Exposure on film is more logarithmic than linear; that is, when you give it more and more light, it slows down in its reactiveness to the exposure instead of continuing up and reaching complete overexposure right away. Of course, the opposite is true for digital, because exposure is much more linear on a digital sensor. So if there is a very bright sky in your photo, it is probably going to be overexposed, and it will look pure white.