Algae can be useful in many different situations. Algae are for instance used as food for humans as well as for live stock, and it is also included in various health products and cosmetics. Seaweed is predominately gulped down in South-East Asia, especially in China, Japan, and Korea, but it is becoming more and more popular outside this range for each year that passes.
If you want to include more algae in your diet you can for instance try red algae from the genus Porphyra. In Asian cuisine, this alga is commonly referred to as nori. It is not commonly eaten fresh; it is instead harvested, dried and pressed into thin sheets. These sheets are then used in all sorts of dishes, from sushi and soups to sauces and condiments. The two most commonly used species of red algae are Porphyra yezoensis and Porphyra tenera.