What is a prime lens?

A prime lens is characterized by having a fixed focal length, which means it does not zoom in or out. This design results in certain advantages, such as typically better optical quality and larger maximum apertures compared to zoom lenses. Because the focal length is fixed, photographers must physically move closer or further away from their subjects to achieve the desired composition. This fixed nature encourages a more thoughtful approach to framing and can help develop a photographer's skills in understanding perspective and composition.

The other options relate to different types of lenses or characteristics that do not apply to prime lenses, such as zoom capabilities or specific uses for certain genres of photography.