What is the chaotic movement of particles of matter called?

Chaotic motion in physics is divided into two branches: thermal motion; “Brownian motion”. The rate of chaotic movement varies with temperature. The higher it is, the faster the speed of propagation of particles in the body and the more chaotic their movement. Although both of them refer to the concept of “chaotic movement”, their meaning is slightly different. Brownian motion is responsible for the motion of visible particles that can be weighed in matter; thermal – the movement of particles of the body itself, which are not visible. But one way or another, thermal motion is the cause of Brownian motion.