Cameras today do such a good job with exposure that we start expecting them to do great with every scene. But sooner or later, you'll run into a scene that causes you and the camera problems. You don't get an exposure that gives the results you need. That's disappointing.
This is most common when dealing with a very contrasty scene, where the brightest parts of the scene are very bright and the shadows are conversely quite dark. Since our eyes are so adaptable, we see detail in the bright areas and in the dark shadows at the same time. There's no camera that can match our capabilities. The camera is limited in its response to that scene, and only can deal with what its technology allows.
When you're confronted with such a situation, it helps to recognize that the camera can't expose that scene to match what you see with your eyes. You can see such problems when you look at the image played back on your LCD and it shows up with contrasty light rather than a nice-looking subject.
So, now that you recognize a problematic scene with bright areas and dark shadows, what do you do? What's the correct exposure, and how do you arrive at that? There are four important working options, plus one idea that doesn't work. First, the non-working of the five.