The notations m.s-1, m s-1, and ms-1 all represent the same unit of measurement for velocity or speed, specifically meters per second. The "m" stands for meters, while "s" indicates seconds. The notation m/s is the standard way to express this unit, with 1/s being equivalent to s-1. Understanding these notations is essential in the context of physics and motion. All variations ultimately convey the same concept of measuring speed.