Rechtecken

Rechtecken is not a standard term in German for a geometric shape. The closest common form is Rechtecke, the plural of Rechteck (rectangle). In written German, Rechtecken may appear as a misspelling or as an nonstandard inflection; the correct plural for the shape used in geometry remains Rechtecke. The term may also occur in compound names or dialectal usage, but it is not widely accepted as a separate technical term.

In geometry, a rectangle is a quadrilateral with four right angles. It is a parallelogram, so opposite sides are parallel and equal in length. The diagonals are equal in length and bisect each other. If the lengths of adjacent sides are l and w, the area is A = l × w and the perimeter is P = 2(l + w). Rectangles can be axis-aligned or rotated; when a rectangle’s sides are parallel to a given coordinate system, it is often described as axis-aligned.

Rectangles appear in many contexts, including architecture, floor plans, tiling, screen displays, and bounding boxes in computer graphics. The concept of a right angle underlies the rectangle and contrasts with acute or obtuse angles. See also: Rechteck, Quadrat, Parallelogram, Right angle.