Here are some internal combustion piston engine basics for beginners!

Cylinder Bore- the diameter of a single cylinder

Stroke- the distance the piston travels from the top to the bottom commonly referred to as TDC top dead center and TBC top bottom center

Piston- a short cylinder that fits snug within the engines cylinder which moves up and down against a liquid or gas (in an engine case a fuel air mixture)

Crankshaft- a shaft that turns reciprocating motion of a piston(s) into rotational motion

Rpm- an abbreviation for revolutions per minute, mostly referring to the rotations per minute the crankshaft is spinning

Horsepower- horsepower is a unit of measurement equivalent to 550 foot pounds per second

Torque- a twisting force, in a engine it is the force of the piston turning the crankshaft