Overview of 3D printing.

<p>(<b>A</b>) A 3D model can be generated and visualized in a wide range of software packages. 3D model available under Creative Commons license via <a href="http://www.thingiverse.com" target="_blank">Thingiverse.com</a>, courtesy of artists Barak Moshe and <a href="http://www.faberdashery.co.uk/" target="_blank">Faberdashery</a>. (<b>B</b>) The surface topology is simplified to a mesh comprising a series of 3D coordinates (vertices) and the triangles (faces) that connect them. (<b>C</b>) The surface mesh is computationally sliced layer-by-layer to calculate machine instructions suitable for 3D printing. Machine instructions can be visualized en face or in cross-section (inset). (<b>D</b>) 3D printing via melt extrusion (inset) can easily achieve layer heights which surpass the resolution of human fingerprints. Scale bar = 1 mm. (<b>E</b>) A selection of the diverse parameter space of 3D printing technologies. Many dozens of different combinations are in practice today.