# stochastic process

A stochastic process is any process governed by the laws of probability:
for example, the Brownian motion of the submicroscopic particles in a colloidal solution (see colloid).
Most stochastics involve time. In the case of particles, the state of
the system at a time *t* is a random variable, *x*(*t*).
In mathematics, particularly statistics,
a stochastic is a family of random variables. The price of a stock is often
modeled as a stochastic process.