They are equations that 'summarise' experimental findings about all things to do with electricity.

Together, they describe/allow us to predict how things to do with electricity will behave.

For example, take the famous equation F=ma.

This describes the relationship between mass, force, and acceleration. With it, we can predict how a certain mass will accelerate depending on the force we apply to it, or any other variation.

Maxwells equations are the same, but much more complex, since electricity and electrostatics are complicated.