PLA (Polylactic acid or polyactide) is a biodegradable polyester. PLA is useful in a broad range of printing applications, has the virtue of being both odorless and low-warp, and does not require a heated bed. PLA filament is also one of the more eco-friendly 3D printer materials available; it is made from annually renewable resources (corn-starch) and requires less energy to process compared to traditional (petroleum-based) plastics. Outside of 3D printing, PLA plastic is often used in food containers, such as candy wrappers, and biodegradable medical implants, such as sutures. PLA filament for 3D Printing is available in a wide range of colors.

You'll be hard pressed to find true PET (Polyethylene terephthalate) filament, as most PET filaments are actually copolymers - PET with an extra molecule. The most common, PETG filament, is an industrial strength filament with several great features. Figuratively speaking, it combines the ease of use of PLA filament with the strength and durability of ABS filament. First, its strength is much higher than PLA and it is FDA approved for food containers and tools used for food consumption. PET filament is not biodegradable, but it is 100% reclaimable. It's known for its clarity and is also very good at bridging.

TPU (Thermoplastic Polyurethane) is an elastic, oil/grease resistant, and abrasion-resistant material with a shore hardness of 95A. TPU Plastic has several applicable uses including automotive instrument panels, caster wheels, power tools, sporting goods, medical devices, drive belts, footwear, inflatable rafts, and a variety of extruded film, sheet and profile applications. It is also commonly used in mobile phone cases.

ASA (Acrylonitrile styrene acrylate) was developed as an alternative to ABS. With a number of additional features, like improved weather resistance and resistance to yellowing from UVs, making it an excellent choice for parts or prints meant for outdoor use. Where white ABS will turn a pale yellow over time, ASA will remain a bright white for much longer.

ABS (Acrylonitrile Butadiene Styrene) is another commonly used 3D printer material. Best used for making durable parts that need to withstand higher temperatures. In comparison to PLA filament, ABS plastic is less "brittle" and more "ductile." It can also be post-processed with acetone to provide a glossy finish.

Nylon is an incredibly strong, durable, and versatile 3D printing material. Flexible when thin, but with very high inter-layer adhesion, nylon lends itself well to things like living hinges and other functional parts. Nylon filament prints as a bright natural white with a translucent surface, and can absorb color added post process with most common, acid-based clothing dyes or synthetic cloth specific dyes. Nylon filament is extremely sensitive to moisture.