A pulley is a simple machine that that runs a cord through a wheel and axle in order to lift an object with less effort. Multiple pulleys may be used in a sequence to make the work even easier.
inclined plane
An inclined plane is a flat surface that has been raised on one end to create an angled slope. By using an inclined plane, less work is required compared to lifting straight up.
screw
The screw is basically an inclined plane wrapped around a cylinder. All screws have linear motion.
wheel and axle
The wheel and axle work by rotating together to reduce the amount of work in moving an object.
wedge
A wedge is a portable inclined plane that when force is applied to the blunt end, the narrow point drives away with a lot of power.
lever
A lever is a beam that is on top of a fulcrum allowing leverage to lift heavier objects with less force.