Why did photosynthesis appear?

First, let’s remember what photosynthesis is in essence. It is a complex process of creating organic matter. This is the synthesis of glucose, which serves as a source of energy for almost all living things. That is, photosynthesis is one of the reasons for the emergence and development of life. It was photosynthesis that made it possible for new organisms to develop. Without this process, it is impossible to obtain glucose in other ways. How exactly this process appeared is impossible to know. But we know that it appeared first in some bacteria.