Divergence is a mathematical operator that measures the magnitude of a vector field's source or sink at a given point. In simpler terms, it helps us understand how much a field is expanding or contracting in space. For example, in physics, the divergence of a velocity field can indicate how fluid is flowing in and out of a region. In the context of vector fields, divergence is often represented by the symbol ∇·F, where F is the vector field. A positive divergence indicates a source, while a negative divergence indicates a sink. This concept is crucial in various fields, including fluid dynamics and electromagnetism.