A fuel injector is an essential component of a combustion engine that delivers fuel to the engine's cylinders in a precise and controlled manner. It sprays fuel into the intake manifold or directly into the combustion chamber, allowing for efficient combustion and optimal engine performance.

A high-pressure pump is a component that increases the pressure of a fluid, typically a liquid, to high levels. In the automotive industry, high-pressure pumps are often used to deliver fuel to direct injection systems in engines, where the fuel needs to be pressurized to very high levels for efficient combustion. High-pressure pumps can also be used in other industries, such as in manufacturing processes that require the precise application of fluids at high pressures.