Both moses and select (sel) are important for signal flow and control. Both have two inlets, as well as two outlets. If the second inlet was connected, it would override the control value, which is 5 in the objects below.
Moses will sent the input number to left outlet if that number is less than the control value. Otherwise, it will send it to the right outlet.
Select will send a bang to left outlet if the number is equal to the control value. If not, it will send a number to the right outlet.