APA (American Psychological Association) is the most common and wildly-used citation style in the world to list and introduce biographical sources or references in academic writing, other well-known citation styles include MLA and Chicago. APA is used in Education, Psychology, and Sciences and is an author-date style.
There are several different ways to cite a source in academic writing. In the past, every subject and specialty has had its own rule for referencing, but today there is a greater tendency among universities and colleges to choose a common method.