Black holes in binary systems can be detected from their broadband emission during episodes of matter accretion from their companion stars. In recent years, the ability to perform multifrequency observations of black hole binaries has led to significant advances in revealing the underlying emission processes and physical properties in these systems. The optical and infrared observations are important for determining the system parameters, such as the companion star type, orbital period and separation, inclination angle, and the black hole mass. The radio observations are useful for studying high-energy electron acceleration processes, jet formation, and particle transport. X-ray and gamma-ray observations probe the inner accretion disk region and the fundamental physics of the accretion disk under extreme conditions of temperature, pressure, and gravitational stress.