It's a neuromuscular relearning process which helps to create new or improve old connections between the brain and muscles. We can also say it's an approach that we use to learn new ways of moving. Another aspect is about working with the nervous system. With somatic practice you can switch from sympathetic mode to parasympathetic mode. It means you can voluntarily switch your state to the resting and recovery mode at the end of the day or whenever you need to do it.
As our brains are multifunctional organs that we use either to move or think or create something new, somatic practises are also can be used in many different ways.