Here you see the 3 phases of the brushless DC (BLDC) motor
Red at 0 degrees, blue at 120 degrees, green at 240 degrees
These are represented in the animation by the 6 coloured "doughnuts"
They are "solenoids" or coils of wire
There are 6 since there are 2 for each phase on opposite sides of the rotor
so you have a complete magnetic field passing through the center of the motor
in 3 directions at 120 degrees to each other.
We have the rotor which has a fixed magnet (show above spinning as shaded grey) and would be attached to the output shaft.
The three phases red, blue and green are each producing an alternating field
and the three together produce a rotating field
which pulls the rotor magnet round and thus the shaft.