The Leica M4 is a 35mm rangefinder camera introduced in 1967 by Leica Camera AG. Known for its compact design and robust build quality, it features a mechanical shutter and a bright viewfinder, making it popular among street and documentary photographers. The M4 allows for interchangeable lenses, enhancing its versatility. This model was the first in the M series to include a film loading system that simplified the process. The Leica M4 is celebrated for its precision engineering and image quality, contributing to its status as a classic in the world of photography.