Your guide to consumer 3D printer filament  
3D printing has never been far from the tech headlines this year. If you want to get involved with the additive manufacturing revolution, you will have to learn a few things about the process. One of the most important things to understand is the difference between different types of filament.
This is the material that runs through the nozzle and forms the object on the building platform below. The consumer level machines generally specialise in two types of filaments: ABS and PLA. Both of these materials have their own advantages and disadvantages and are suited to different things and knowing about this will be crucial to getting your 3D objects printed properly.
Also known as Acrylonitrile Butadiene Styrene, ABS is a petroleum based material that is perfect for durable, tough objects. The cheaper of the two filaments, its flame resistant toughness makes it a great choice for protective clothing, pipes, appliances and car or machine parts. Objects can be sanded down post print, so getting a nice smooth finish is possible.
ABS does, however, come with certain issues. First off, it doesn't smell great while being extruded so you will need a well ventilated area to work in. It's toxic too, so can't used for any kind of food container. It doesn't biodegrade either, though certain machines are being developed that might allow you to recycle old ABS objects.
Polylactic Acid or PLA is made from corn starch, sugar cane, tapioca roots and potato starch. This means it comes with a pleasant smell, biodegrades and can be used for food packaging or utensils. Yet it is also somewhat brittle when cooled and takes a long period of time to cool down.
This means using it for machine components that will be put under a heavy amount of pressure or in a high temperature is not really possible. Also, sanding it down post printing is not really possible.
It is, however, good for medical implants as it degrades eventually within the body. Disposable clothing or any hygiene related products is also printable with PLA.