Flax seed has been a widely grown crop for thousands of years, and it is believed that it was one of the first plants that humans domesticated and farmed. It is one of the most versatile plants in the world, capable of being made into fabrics (especially linen), medicine, high-quality paper (often used for money), soap, and all sorts of other things. The most useful thing that flax seed can be made into, however, is linseed oil (also known as flaxseed oil).

Linseed oil is one of the most commonly used vegetable oils. As well as being used in food, it has also been used as a finish and polish for wood and painted surfaces, in putty and caulk, and perhaps most notably in linoleum, which many people wrongly believe is made from man-made materials. Linoleum is actually wood or cork dust on canvas, overlaid with solidified linseed oil, making an all-natural floor covering that is especially suitable for people with allergies. Wood is also treated with linseed oil when making bats for some sports, including cricket.

The popularity of linseed oil for food preparation has been steadily growing again, as people have been paying more attention to the benefits of omega-3 fatty acids, which the oil is rich in, while also being low in the omega-6 fatty acids that many people are now trying to avoid. Some have come to use it as an alternative to cod liver oil, and it is readily edible poured straight onto salads it has a nut-like flavour. If you do not like the taste, though, capsules of the oil are also available. As most of the worlds flax seed is cultivated in Europe, it is much cheaper there than elsewhere, but as a rule it should be cheaper than cod liver oil in almost all countries.