How many wavelengths does a laser consist of?

A laser consists of a single wavelength, which characterizes its monochromatic nature. This means that the light emitted from a laser is of one specific wavelength and color, allowing for the production of highly focused and coherent light. The coherence of a laser beam is critical for its applications in various fields, such as medicine, communications, and manufacturing, as it enables precision and effectiveness in procedures like laser hair removal or surgical operations.

The presence of a single wavelength is what differentiates lasers from other light sources, which may emit multiple wavelengths simultaneously, leading to a broader spectrum of colors.