multiplayer, Call of Duty 4: Modern Warfare, Macintosh, online gaming, dedicated servers, FPS, action-packed, urban warfare, military simulation, team-based, search and destroy, deathmatch, capture the flag, modern combat, tactical gear, realistic weapons, soldier avatars, map variety, server list, smooth gameplay, voice communication, clan support, modding community, custom maps, high-resolution textures, dynamic lighting, shadow effects, particle effects, anti-cheat system, leaderboard rankings, cross-platform play, server browser, ping indicator, first-person view, immersive sound design, network optimization.