The jointer plane is a type of hand plane used primarily to straighten the edges of boards in the operation known as jointing

Edge jointing

Edge jointing or just jointing is the process of making the edge of a wooden board straight and true in preparation for subsequent operations, often ultimately leading to joining two or more components together. Traditionally, jointing was performed using a jointer plane...

. A jointer plane may also be used to flatten the face of a board. Its long length is designed to 'ride over' the undulations of an uneven surface, skimming off the peaks, gradually creating a flat surface. In thicknessing or preparing rough stock, the jointer plane is usually preceded by the jack plane

Jack plane

A jack plane is the general-purpose bench plane, used for general smoothing of the edges, sizing of wood and jointing edges. Jack planes are about 12-15 inches long, and the blade can have either a slightly circled edge for smoothing stock, or a curved edge for jointing stock.In preparing stock,...

 and followed by the smoothing plane

Smoothing plane

A smoothing plane or smooth plane is a type of bench plane used in woodworking. The smoothing plane is typically the last plane used on a wood surface - when used properly, the finish it gives will be far superior to that made by sandpaper or scrapers...

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Jointer planes are typically 20 to 24 in (508 to 609.6 mm) long. There is also a shorter version of the jointer plane known as the fore plane which is around 18 inches (457.2 mm) long.