This is the starting point for all programs. Blocks connected to the starting point will be downloaded to the NXT when you use the controller to hit Download, Download and run, or Download and run Selected.
If you click the starting point, you can type a note in the configuration panel that will be saved with the program.
You can also use the starting point to create additional sequence beams that will allow your program to run simultaneous tasks. For example, you might have the main sequence beam in your program controlling a robot’s forward motion but have a second sequence beam controlling a robotic arm that sits on top of the robot.
Create a parallel sequence beam by moving the mouse pointer over the starting point (or over the wire stub), and pressing and holding your mouse button while you move the mouse upwards or downwards. This will draw out a sequence beam that can be connected to programming blocks. When you download and run the program, the blocks on both sequence beams will run in parallel. You can use data wires to have the blocks on both sequence beams communicate with each other.
You can also start a new sequence beam later in your program (i.e., not from the starting point). Do this by holding down the Shift key and moving your mouse pointer perpendicular from a position on the main sequence beam.