Unity has two netcode frameworks for creating real-time synchronized gameplay in multiplayer games.

Netcode for Entities is a server-authoritative networking solution with a client prediction framework for multiplayer games built using the Data-Oriented Technology Stack (DOTS). Use Netcode for Entities to create high-performance multiplayer games with large numbers of players and complex game logic.

Netcode for GameObjects is a high-level networking library that abstracts networking logic and allows you to send GameObjects and world data across networking sessions to many players at once. Use Netcode for GameObjects to create multiplayer games with a smaller number of players and less complex game logic, or to add multiplayer functionality to an existing single-player game built using GameObjects.

If you're unsure which netcode framework is right for your game, you can use the Multiplayer Center in the Unity Editor to get a recommendation based on your game's needs.