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How does this mean that the charge is conserved in the neighbourhood of any point?

I am currently studying the textbook Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction of Light, 7th Edition, by Max Born and Emil Wolf. In section 1.1.1 Maxwell's equations, the authors say the following:

$$\dfrac{\partial{\rho}}{\partial{t}} + \text{div} \ \mathbf{j} = 0 \tag{5}$$ By analogy with a similar relation encountered in hydrodynamics, (5) is called the equation of continuity. It expresses the fact that charge is conserved in the neighbourhood of any point.

$\rho$ is defined to be the electric charge density, and $\mathbf{j}$ is defined to be the electric current density.

So (5) is saying that the change in the electric charge density with respect to time plus the divergence of the electric current density is equal to zero. But how does this mean that the charge is conserved in the neighbourhood of any point?

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