Dynamic stretches bring warmth and movement to the muscles and ligaments, without fully stretching them. Repetition of a dynamic stretch movement (like the ones described above) increases range of motion and literally warms the muscles, which is what most people want to do before engaging in their exercise.
Static stretches are held in stillness for anywhere from 10 seconds to several minutes. They allow the muscles and ligaments to slowly stretch to their full length. This helps to increase flexibility. It also aids release of lactic acid after workouts (so you don’t feel the burn as much the next day)