Underwater Acoustic Communication is a method used to transmit information through sound waves in water. This technique is essential for various applications, including submarine communication, oceanographic research, and underwater robotics. Sound travels better in water than radio waves, making it the preferred choice for long-distance communication underwater. The process involves sending and receiving acoustic signals using specialized equipment like hydrophones and sonar systems. These systems convert electrical signals into sound waves and vice versa, allowing for data exchange between devices. Challenges include noise from marine life and human activities, which can interfere with the clarity of the signals.