Nylon is a thermoplastic that is used to make fabric. The resulting fabric is extremely durable, very effective at blocking wind, resistant to molds and fungus, and very lightweight. Its does not have very good insulative properties, however.
Nylon is suitable for wind/water protective outer layers such as windbreakers and treated raincoats. It is also used in making tough ballistic nylon fabric and Cordura (TM) fabric for tactical gear such as backpacks, vests and molle pouches.