Inclined Planes or Ramps Make Lifting Easier

The humble yet immensely important ramp, or inclined plane, is another of the fundamental six simple machines that allows heavy loads to be moved vertically with relatively little effort. They are widely used in many applications from loading goods into trucks to disabled access ramps.

Moving an object up an inclined plane requires less force than lifting it straight up at a cost of an increase in the distance moved. The mechanical advantage for ramps is equal to the ratio of the length of the sloped surface to the height it rises. 
The screw and wedge are other simple machines that can be considered variations on the inclined plane or ramp rather than discrete forms.