1. LEGO® MINDSTORMS® NXT
Move Block

2. Motor versus Robot Direction
When you set a Move or Motor blocks' direction, you are specifying the direction the motor will spin. This may be different than the direction your robot actually moves. Depending on how you build your robotic invention, setting the motors to go forwards may cause your creation to move backwards. The image below shows a motor spinning in the default, forwards direction.

3. Move Block
The letters at the top right corner of the block show which of your NXTs ports will be controlled.
This icon shows which direction your robot will go.

4. Move Block
This icon shows the power level. Your robot’s speed may also be affected by other conditions, like the surface it is moving over or whether it is moving up or down a slope.
This icon shows whether you have set the Duration property to unlimited, degrees, rotations, or seconds.

5. set to "stop
This icon shows that the Direction property is set to "stop". This setting will stop all motors.

6. Select the motors you would like to control
Select the motors you would like to control. If you choose to control two motors (Example: B & C), the motors will be synchronized, going forward or backwards at exactly the same power. If you select three motors, motors B & C will be synchronized.
Choose whether the motors will go forward, go backwards, or stop. Selecting Stop will also reset the motors. (See also the Reset Motor Block file.)
If you’re using two motors to drive a vehicle (with one on each side), the Steering slider will appear with the chosen port letters indicated at each side. Move the slider to set a curved path for your robot. With the slider all the way to either side, your vehicle will spin in place.
This slider and the editable input box will let you set the power level [0-100%].

7. Using the Duration pull-down menu, you can set the motors to run for an unlimited interval or for a set number of seconds, rotations [default] or degrees. By choosing Time, Rotation or Degrees you can control how far your robot will travel. (See the Tip below.)
Choose whether the motors will brake or coast after they’ve finished their action. If you want your robot to stop precisely at an exact location, set the motors to brake. Setting your motors to brake will also keep your robot from slowly rolling backwards on a slope but the setting will wear out the NXTs batteries quicker because the motors are doing work to keep the robot in place.
The feedback boxes will count how many degrees or full rotations your motors turn. Press the reset button to return the values to zero. (To receive feedback, make sure that the motors are connected to the chosen ports and that communication has been established with the NXT.)

8. Motor versus Robot Direction
When you set a Move or Motor blocks' direction, you are specifying the direction the motor will spin. This may be different than the direction your robot actually moves. Depending on how you build your robotic invention, setting the motors to go forwards may cause your creation to move backwards. The image below shows a motor spinning in the default, forwards direction.