These different types of lighting create different gradients and colours of light giving an image more meaning and depth. The way the light is enables the image to be more interesting and direct to what you want for your shoot.
"But we can’t live in the light all of the time… You have to take whatever light you can hold into the dark with you." - A Great and Terrible Beauty by Libba Bray Photo by Nico Nordström. <-- This is beautiful, and so true.