If you're a budding photographer like me, then you will find this article very insightful.
If you're shooting portraits, lighting has more of an impact on your final result than anything else. Yes, it's important to get subtle skin tones the right color, and sure, you might want to consider whether you want more or less depth of field, but it's lighting that will do the most to make a person look more pleasing.
Of course, you can buy expensive lighting rigs or multiple flash units and concoct carefully constructed three-point lighting schemes. Using studio lighting (or multiple handheld strobes) definitely gives you the greatest control and flexibility. Or you can save yourself a lot of money and use available light.
Enjoy!