# Fields

Electromagnetic theory is essentially a study of certain fields. If at each point of a region, there is a value for some physical function, the region is called a field.

Fields may be classified as scalar fields and vector fields.

# Scalar Fields

If the value of a physical function at each point is a scalar quantity, the field is known as a scalar field.

Some examples of scalar fields are temperature distribution in a building, sound intensity in a theatre, height of the surface of the earth above sea level and electric potential in a region.

A scalar field independent of time is called a stationary or steady-state scalar field.

# Vector Fields

If the value of a physical function at each point is a vector quantity, the field is known as a vector field.

Some examples of vector fields are gravitational force on a body in space, wind velocity in the atmosphere and the force on a charged body placed in an electric field.

A time-independent vector is called a stationary vector field.