Changes

The '''screw''' is a [[simple machine]] often used in conjunction with a [[screwdriver]] to bore into a piece of [[wood]].  A screw's mechanical advantage is equal to the circumference of the screwdriver handle divided the the screw's pitch, the distance from one thread to the next.<ref>http://www.cosi.org/files/Flash/simpMach/sm1.swf</ref>

The '''screw''' is a [[simple machine]] often used in conjunction with a [[screwdriver]] to bore into a piece of [[wood]].  A screw's mechanical advantage is equal to the circumference of the screwdriver handle divided by the screw's pitch, the distance from one thread to the next.<ref>http://www.cosi.org/files/Flash/simpMach/sm1.swf</ref>

A screw is a practical application of the [[incline plane]].  

A screw is a practical application of the [[inclined plane]].  

==References==

==References==