Single vs. multiple light sources

 With a portrait that is lit with only one light source it creates nice shadows on the outline of her body and also creates a hot spot around her forehead.

With a portrait that is lit with multiple light sources as you can see the side of her face is lit but you can also see a little bit of light on the back of her head. Using more than one light source can make it easier to evenly light a photograph.

 When using soft light in portraits it makes colors pop and skin look softer and more smooth it shows less curves and makes the picture more dramatic in some cases

When using hard light in portraits the light tends to make the picture very contrasted and it exagerates the curves a lot more.