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+# Websocket Data
+
+This document describes the JSON object send back from the simulator command server.
+
+Fields:
+
+* ptsx (Array<float>) - The global x positions of the waypoints.
+* ptsy (Array<float>) - The global y positions of the waypoints. This corresponds to the z coordinate in Unity
+since y is the up-down direction.
+* psi (float) - The orientation of the vehicle in **radians**.
+* psi_converted (float) - The orientation of the vehicle in **radians** converted from the Unity format to the standard format expected in most mathemetical functions (more details below).
+* x (float) - The global x position of the vehicle.
+* y (float) - The global y position of the vehicle.
+* steering_angle (float) - The current steering angle in **radians**.
+* throttle (float) - The current throttle value [-1, 1].
+* speed (float) - The current velocity in **mph**.
+
+
+### Unity Degree Conversion
+
+The degree representation does not correspond to the following representation below, standard in most mathematical functions. `psi_converted` is the mapping to the below orientation representation.
+
+```
+//            90
+//
+//  180                   0
+//
+//            270
+```