# Common This section contains common API that have almost atomic significance for all projects. - Json: Json serialization engine. Json is used to store emulator settings, as well as for the JDI system (Json Debug Interface). - Spinlock: Mutually exclusive access synchronization. - Thread: Portable threads. - Jdi: Json Debug Interface. More information can be found in [JsonDebugInteface.md](https://github.com/ogamespec/dolwin-docs/blob/master/EMU/JsonDebugInterface.md) - File: File utilities - String: String utilities