These two areas provide information about Unity's networking system, which was introduced during the Unity 5 release cycle. The information present will depend on whether the application is using the High-Level API (HLAPI) or Transport Layer API (TLAPI) provided by Unity. HLAPI is an easier-to-use system for managing player and GameObject network synchronization automatically, whereas TLAPI is a thin layer that operates just above the socket level, allowing Unity developers to conjure up their own networking system.

Optimizing network traffic is a subject that fills an entire book all by itself, where the right solution is typically very dependent on the particular needs of the application. This will not be a Unity-specific problem, and, as such, the topic of network traffic optimization will not be explored in this book.