From the name itself, a 2D shape is a shape having only two dimensions, such as length and width. This means the shape is occupying only one plane and has no depth.
In math, 2D shapes are also called polygons. These are categorized into ellipses and circles, triangles, quadrilaterals and squares, pentagons and hexagons, and so on. There is no limit to the number of sides a polygon can have.
In art, 2D shapes can either be geometric or organic. Tools are needed in making geometric shapes, such as circles and triangles. On the other hand, organic shapes are those found in nature, such as the shapes of clouds.
2d shape is a dimension.
http://wiki.answers.com/Q/What_is_the_definition_o...

1. Identify the height. The height is commonly described as the length of a shape from top to bottom. However, this definition is only true when the shape is drawn perfectly upright
http://www.ehow.com/how_8730224_interpret2dshape...

Assuming the ramp has sufficient friction and is smooth, I think the answer is probably to put all the mass in a circle, and then extend the circle with an series of infinitessimally
http://www.quora.com/Physics/Whatisthe2Dshape...

Septahedron.
http://wiki.answers.com/Q/What_2D_shape_has_at_lea...
