diff --git a/trajectory_prediction/readme.txt b/trajectory_prediction/readme.txt
new file mode 100644
index 0000000..873411e
--- /dev/null
+++ b/trajectory_prediction/readme.txt
@@ -0,0 +1,12 @@
+1. prediction_train.zip: Trainning data for trajectory prediction. 
+    Each file is a 1min sequence with 2fps. 
+    Each line in every file contains frame_id, object_id, object_type, position_x, position_y, position_z, object_length, object_width, object_height, heading. 
+    For object_type, 1 for small vehicles, 2 for big vehicles, 3 for pedestrian, 4 for bicyclist and 5 for others. We consider the first two types as one type (vehicles) in this challenge.
+    Position is in the world coordinate system. We just think the traffic in a 2D plane and ignore its position_z.
+    The unit for the position and bounding box is meter.
+    The heading value is the steering radian with respect to the direction of the object. 
+    You do not need to use all the info we provide. The output of your prediction is just the position_x and position_y in the next several seconds.
+    
+2. prediction_test.zip: Testing data for trajectory prediction. 
+    Each line in the prediction_test.txt contains frame_id, object_id, object_type, position_x, position_y. 
+    Each six frames in the prediction_test.txt is a testing sequence. Each sequence is independent. You need read the file carefully.
\ No newline at end of file