Agar-Agar
Agar-Agar is a vegetarian, jelly-like gelatin substitute derived from red algae. It is sold as powder or flakes and is flavorless, making it an excellent thickening and gelling agent for desserts, candies, and firm jellies (like yokan in Japan).

Alaria
Alaria is a brown seaweed, often called wing kelp. It has a high nutritional value and a pleasant, nutty flavor with a chewy texture. It is typically dried and sold as flakes for seasoning, or used in soups and as a vegetable substitute.

Aonori
A distinct category of dried green seaweed (typically Monostroma or Enteromorpha) that is processed into a fine powder or flakes, used exclusively as a seasoning and garnish on Japanese dishes.

Bladderwrack
Bladderwrack is a brown seaweed known for its high iodine content. Historically used to treat goiter, it is primarily consumed today as a herbal supplement in powdered or capsule form, rather than as a culinary ingredient, due to its strong flavor.

Chlorella
Chlorella is a single-celled green microalga sold as a dietary supplement in tablet, capsule, or powder form. It is a complete protein and a potent source of vitamins and minerals, commonly mixed into smoothies or juices for a nutritional boost.

Dulse
Dulse is a soft, red alga that is hand-harvested along Atlantic and Pacific coasts. It is known for its chewy texture and a naturally salty, smoky, or slightly bacon-like flavor when fried. It is eaten dried as a snack, used as a seasoning, or added to salads and soups.

Hijiki
Hijiki is a dark brown seaweed with a distinct, earthy flavor and a firm, slightly crunchy texture. It is often simmered with soy sauce and vegetables (e.g., carrots and shiitake) to create a popular Japanese side dish known for its high mineral content.

Irish Moss
Irish Moss (Chondrus crispus) is a red seaweed rich in carrageenan, a natural hydrocolloid. It is traditionally boiled to create a nutrient-rich, jelly-like thickening agent for puddings, shakes, and soups, and is used commercially as a stabilizer in dairy products.

Kombu
Kombu (or kelp) is a thick, dark brown seaweed essential to Japanese cooking. It is the primary ingredient in dashi (soup stock), imparting a deep, savory umami flavor. It is also cured, pickled, or simmered with vegetables. Rich in iodine and minerals.

Mozuku
Mozuku refers to various types of Japanese brown algae, notable for its slippery, stringy texture and mild, slightly vinegary flavor. It is typically served dressed in a light vinegar sauce (sunomono) or added to soups, and is rich in the polysaccharide fucoidan.

Nori
Nori is a dried red seaweed, characterized by its paper-thin sheets, dark green color, and savory, umami flavor. It is most famous for wrapping sushi and onigiri, but is also crumbled over noodles and rice for added flavor and nutrients.

Sea Lettuce
Sea Lettuce (Ulva) is a delicate, bright green algae with a texture resembling garden lettuce and a mild, slightly pungent flavor. High in protein and iron, it is typically used raw in salads, dried as flakes for seasoning, or in light soups.

Spirulina
Spirulina is a blue-green microalgae sold as a dietary supplement in powder or tablet form. It is one of the most protein-dense foods, providing all essential amino acids, and is known for its strong, earthy flavor and characteristic blue-green color.

Wakame
Wakame is an edible sea kelp with a subtly sweet, distinctive flavor and a silky, tender texture when rehydrated. It is most commonly served in miso soup or in cold salads (e.g., sunomono), valued for its high calcium and iron content.