Linen is arguably the oldest fabric known to man, the great-grandfather of all fabrics. Linen that is 11,000 years old is still being discovered. Linen is grown as flax and is the fibre that is the core of the plant. The fibres are long and when spun into yarn they are incredibly strong. The flax is soaked for weeks on end, eventually revealing the fibre inside, this part revealed fibre is then scorched or hacked to get rid of the outer layer and leave only the inner fibre.
The fibres are then ready for spinning into yarn and weaving.
The weaving process on modern power looms is as complex as that for wool and cotton producing a myriad of designs. Flat plain fabrics are often beetled. This is a process of the whole fabric being hammered with small wooden mallets that produce a glistening sheen. The linen yarn is thicker than cotton, therefore the yarn count (the number of yarns per square inch) is much lower, so a yarn count of 80-150 is fairly typical.
Linen typically creases easily but gets softer the more it is washed or cleaned. Go with the creases, they are a badge of honour.
Linen can also be blended with other yarns such as wool or cotton to give a more durable linen effect.