From flax to linen. Linen is a very durable, strong fabric, and one of the few that are stronger wet than dry. The fibers do not stretch and are resistant to damage from abrasion. In the past, linen was also used for books as the paper made of linen can be very strong and crisp, which is why the United States and many other countries print their currency on it. Linen is a preferred support for oil painting for its strength, durability and archival integrity.