What role do the seas play in people’s lives?

The seas play a huge, significant role in human life. The sea is an excellent supplier of oxygen and maintains the oxygen-carbon dioxide balance necessary for life on Earth. On the shores of the seas, there are various resorts and sanatoriums where people with various diseases are treated, there are many resort areas for recreation. The maritime climate is good for everyone. At the bottom of the seas, there are rich reserves of oil that are extracted and used in various fields of activity, as well as marine plants, fish, shellfish that we feed on.