Not to trying to be sarcastic, but it's called 3 dimensional artwork. The phrase '3D artwork' is to vague to place a specific label on it since it can cover sculptures, pottery, paintings that have a 3D perspective, digital 3D art, and so on.
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three-dimensional artwork
A pyramid
No. A polygon is a 2-dimensional figure. A polyhedron is 3-dimensional.
3-dimensional, if it's in real life. If it's merely a picture, then it's a 2-dimensional object depicting something that's 3-dimensional.
A painting is a two dimensional artwork; a sculpture is a three dimensional artwork.
The differences between 2-dimensional and 3-dimensional artwork are the differences between a painting and a sculpture. A painting, a drawing, a photograph, are all 2-dimensional, existing on a flat canvas or piece of paper, or on a wall, etc. A sculpture, a mobile, etc., are 3-dimensional objects that may be hung from or stand on a surface, but have length, width and height.
A 3-dimensional parallelogram is a parallelepiped .
A 3 dimensional figure
Two dimensional artwork is the kind of art you typically see in a frame. I.e. it is flat or on one plane. Examples include watercolors, photographs, lithographs, oil paintings, etc. This artwork has a length and a width, but no depth or height.Three dimensional artwork has depth or height in addition to length and width. Examples include sculpture, carvings, ba relief etc.Some people make three dimensional art in a frame (e.g. some collages and some masks). These are still considered three dimensional.
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three-dimensional artwork
three-dimensional artwork
Drawing and painting are two-dimensional, sculpture is three-dimensional.
Paintings before the Renaissance: people saw in only a 2 dimensional figure, but in the Renaissance, people saw art in a 3 dimensional figure. Painters in the Renaissance gave attention to body size, proportions, perspective, and detail.
It depends on what media the artwork is. For two dimensional and digital pieces (and maybe three dimensional, I'm not 100% sure), there is a website called deviantART where you can sell your artwork as posters. You can also auction your artwork on eBay if you request a reasonable price.