PVA (Polyvinyl Acetate) is a water-soluble material that is often used as a support material, but can also be used to print independently.
The recommended printing temperature for PVA is 170-190°C. PVA is a water-soluble filament which means two things, it makes an excellent support material and it MUST be kept dry.
PVA prints translucent with a slightly yellow tint. It is most often used on 3D printers with dual extruders, with one extruder printing a primary material (such as ABS or PLA) and the other printing this easily-dissolved material to provide support for overhanging features.
Check out how great PVA can dissolve as a support structure!