What is the key difference between series and parallel circuits?

The key difference that makes this answer accurate is based on the physical arrangement of the components within the circuits. In a series circuit, components are connected end-to-end in a single path for the current to flow. This configuration means that the same current flows through each component sequentially. If one component fails in a series circuit, the entire circuit is interrupted.

In contrast, parallel circuits connect components across common points, creating multiple paths for current to flow. In this setup, each component operates independently from the others. If one component in a parallel circuit fails, the remaining components can still function, allowing the circuit to continue operating without interruption.

Understanding this fundamental arrangement helps clarify how each type of circuit behaves under different conditions, influencing both current distribution and voltage characteristics across the components.