How does a person use algae?

Man uses seaweed in the chemical industry. They produce iodine, potassium salts, cellulose, alcohol, acetic acid and other substances. Algae is used as fertilizer and feed for livestock. Some types of red algae produce a gelatinous substance called agar-agar, which is necessary in the confectionery, bakery, paper and textile industries. Microorganisms for laboratory research are grown on agar-agar. In many countries, seaweed is used to prepare a wide variety of dishes. They are very useful as they contain a lot of carbohydrates, vitamins, and are rich in iodine. Especially often they eat kelp (seaweed), ulva (sea salad), porphyry, etc. Recently, algae have become widely used in cosmetology. Single-celled green algae – chlamydomonas, chlorella, etc. – are used in biological wastewater treatment. Some unicellular algae are used to produce gaseous fuels (biofuels).