Where are the flak seeds?
Sounds like you mean flax seeds. They are small and brown with a shiny coat. They can be ground and added to things like muffins or bread; they are a good addition to smoothies. They have good Omega oils and well as a lot of fiber. Sometimes they are used for a laxative effect. Another use is to mix with water as an egg substitute. Look for more information on the Whole Foods web site.
I grind them, put them in the freezer and use them as susan g says but also I sprinkle over salads and soups. They are extremely good for you because of their Omega oils. Some people say they use them without grounding them, but the nutrition is lost that way as they don't break down in your system.