Vector analysis is a mathematical tool. Electromagnetic (EM) concepts are conveniently expressed and explained by vector analysis. A “scalar” is a quantity having only magnitude. It is described simply by a number. For example, physical quantities like mass, temperature, time, density, electrostatic potential, length, volume, distance, population, entropy, etc. are scalar quantities.
A “vector” is a quantity having both magnitude and direction. For example, force, velocity, electric field intensity, displacement, acceleration, etc. are vector quantities.
To differentiate between vector quantities and scalar quantities, we show a vector by an alphabet with an arrow over it. For example, and