Moxibustion (Moxa), is an ancient treatment method that's even continued to be used today. The main idea of Moxa, is to help with warming and tonifying an acupuncture point so that it can effect the corresponding meridian channel, and organ.
Guasha is a traditional treatment method that involves stroking of the skin. The goal of this treatment is to continue the stroking motion of the skin until a small raised, rash like red dots appears. This is usually called patechiae which would usually resolve by itself after few days. The idea of this treatment is, that it helps with improving circulation of the body, and moving Qi when its stuck.
Cupping is a popular method for relaxing the muscles, and help circulation in the body. However, that is not the only function of cupping. Depending on where the cups go, there is a significant effect on the channels which can help the Qi and blood move. Cupping can also cause a round patch of patechiae, and would resolve by itself.