The force between two solids in contact that prevents them from occupying the same space. The normal force is directed perpendicular to the surface. The force between two solids in contact that resists their sliding across one another. Friction is directed opposite the direction of relative motion or the intended direction of motion of either of the surfaces. The force exerted by an object being pulled upon from opposite ends like a string, rope, cable, chain, etc.
Tension is directed along the axis of the object.
The force exerted on an object immersed in a fluid. Drag The force that resists the motion of an object through a fluid. Drag is directed opposite the direction of motion of the object relative to the fluid. Lift is generally directed perpendicular to the direction of fluid flow. The force that a fluid exerts when pushed by a propeller, turbine, rocket, etc.