Moments as turning effect of forces
The moment of a force is the turning effect of a force.
A worker applies a force to a spanner to turn a nut.
A force that is applied to an object away from the object's centre makes the object rotate about a fixed point.
The point of an object that does not change position when it experiences a moment is the pivot.
A moment is a vector quantity because it has a size and a direction. Moments can act clockwise or anti-clockwise.
When you open a door the pivot is the hinge which connects the door to the wall. The force is you pushing the door.
For a seesaw the pivot is the central part which is connected to the ground. The force is the weight of the person sitting on the seesaw.