Biographies date back to the times when stories were chiseled into stone by scribes. In the earliest forms, biographies were generally only about extremely famous and powerful people, and were often commissioned by the great person or his family. In the late 18th century, a craze for biography and autobiography began in England, and biographies became more popular than ever before. In the 1920s, there was another intense spate of interest in biographies as they became cheaper to print and to purchase. The 20th century also saw the advent of biography in film form in addition to book form.
A biography is distinguished from other kinds of historical and personal writing in a few ways. A biography covers the entire life (or entire life to date if the subject is still living). If a person writes about a portion of his life but not the whole, this is a memoir, not a biography. A biography is also distinguished from other kinds of historical writing in that it is written in-depth. It covers items beyond the basic facts like genealogy and work history and delves into how the subject felt about his life and work and how others felt and thought about him.
Biographies can be written or filmed. Written biographies can be popular "mass" biographies or academic and serious biographies. Biographies of celebrities with lots of photos or tell-all biographies with an emphasis on scandal fall into the first category. Longer works that examine the lives of artists, politicians, scientists and philanthropists usually fall into the latter category. Written biographies of subjects who are still living are either authorized or unauthorized. An authorized biography is written with the consent and perhaps participation of the subject, while an unauthorized biography is written without the permission or input of the subject. Finally, a sub-category of written biography is the autobiography, which is written by the subject herself.
Most biographies contain a short genealogy toward the beginning, briefly covering the lives of the subjects parents or even grandparents. This helps put the life of the subject in context. Another feature of some, but not all, biographies, are photos of the subject, his family members and sometimes homes where the subject lived.
Biographies can range from about 100 pages to multi-volume sets. For instance, slim paperback biographies of young singers or actors still in their 20s are often published for teen readers. In contrast, Isaac Asimov is known for having written a two-volume autobiography, published in 1979 and 1980, that totaled more than 1,000 pages, with a third volume added in the 1990s.