A log splitter is a piece of machinery

or equipment used for splitting firewood 
from softwood or hardwood logs that have 
been pre-cut into sections (rounds), 
usually by chainsaw or on a saw bench.
 
Many log splitters consist of a hydraulic
 pump or electric motor which then powers
 a hydraulic or electrical rod and piston 
assembly. Generally, these are often rated
 by the tons of force they can generate.

 The higher the force rating, the greater 
the thickness or length of the rounds that
 can be split. The log splitter consists
 of all four major hydraulic components.