A deposit bonus code is a promotional tool used by online casinos and betting sites to attract new players and reward existing ones. By entering a specific code during the deposit process, users can unlock bonuses such as extra funds or free spins, enhancing their gaming experience. These codes often come with terms and conditions, including wagering requirements and expiration dates, so it's essential for players to read the fine print. Utilizing a deposit bonus code can significantly boost a player's bankroll, providing more opportunities to explore games and increase winning potential.