What are the key differences between gta iii and gta online gameplay mechanics?

Grand Theft Auto III established the formula for the 3D open-world Grand Theft Auto series, offering a linear single-player campaign set in three islands of Liberty City. Players control Claude, a silent protagonist navigating a crime-driven narrative with mission-based progression, on-foot and vehicle combat, and a static world that does not evolve between playthroughs. In contrast, Grand Theft Auto Online launched as a separate multiplayer component with no single-player story mode. It supports up to 30 players in shared sessions, features character customization through stats and ranks, includes monetization via microtransactions, and receives regular content updates including new missions, vehicles, and game modes. While both games share core mechanics of vehicle-based exploration and criminal activities, Online introduces cooperative and competitive multiplayer structures, persistent player progression, and a dynamic economy not present in the original GTA III.