Also called triangular paper, a page of traditional isometric paper is printed with a grid-like pattern of vertical and slanting lines occurring at regular intervals. The grid may be simple, with wider space between lines and creating larger triangles, or complex, with lines closer together and producing smaller triangles. However, the distance between lines is uniform on the same page. The gauge of isometric paper is expressed as a measurement of the distance between these lines, such as 5 mm or 1 cm. In a subtler variation, isometric dot paper eliminates the lines, incorporating only dots where lines intersect.
Three different sets of parallel lines are incorporated into the grid on a page of isometric paper. These include vertical lines, lines slanted 30 degrees left, and lines slanted 30 degrees right. A variation of isometric paper, axonometric paper, incorporates vertical lines and lines slanted 45 degrees left and 45 degrees right.
Although the word has several specific applications, at its most basic, isometric is an adjective meaning equal dimensions. An isometric drawing creates three dimensions -- width, height and depth -- but does not create the impression of distance, as a perspective drawing does. For example, in a real-life view of the front of a rectangular building, the rear of the building appears shorter than the front of the building. An isometric drawing of the building would show all heights as equal, regardless of distance.
Designers of all kinds -- including architects, engineers and interior designers -- use this kind of graph paper to create isometric sketches with mathematically correct proportions. A designer might draw on the paper itself, lay a translucent sheet over the isometric paper and trace its lines where necessary, or use an electronic version created on a computer program such as computer-aided design (CAD). Isometric paper is available from art, design and office supply outlets.