Pixel Art is a form of art made by taking blocks and putting them together to form the image of something. In Pixel Art, any block may be used. Although, usually, only wool is used.To the right is an image of a cake with mobs on it. It was made with multiple blocks, including wool, stone and iron.
Many fascinating things have been created, mostly characters from old school games like Mario or Megaman, others can be pixel art of faces or simply things in Minecraft like a stone shovel.
Although wool is mainly used in pixel art, some pro pixel artists will try and get away from it and use other blocks. For some pixel arts, it is best to use the Stained Hardened clay block, to give it that old feeling.
3D Pixel art
3D Pixel art is statues of mostly block like things or structures, such as the regular Minecraft player or a mob, or a companion cube. Also making it can be very hard because it takes a lot of blocks of Wool, Lapis, Redstone, Gold e.g.