Yiannis A. Karatzas was born in Mytilini in 1952. He graduated from the 5th Primary School and then from the 2nd High School for Boys of Mytilini. He studied Civil Engineering at the Technical University of Darmstadt (Darmstadt), West Germany. He worked in the State from positions of responsibility and retired at the end of 2014 as the head of the PE.HO.SCH Directorate. of the North Aegean of the Decentralized Administration of the Aegean.
He has been involved with photography since his student years and is one of the founding members of Foto. Yr. Mytil. (FEM). Since 1979 he has been photographing and documenting the native orchids of Lesvos. He specializes in nature photography in general. Along with the natural, he is also interested in the built environment of Lesbos, recording the original elements of Lesbian Architecture, especially Micro-architecture. His photographs are descriptive and he uses them as a documentation tool for his texts about the natural and built environment of Lesvos, which he deals with systematically.
His writing work includes a series of books and several articles and announcements in Greek and foreign (mainly) scientific journals. These include the book "Lesvos, Nature, and Culture - The Gulf of Kallonis" which has also been published in English, Turkish, and Russian.