First vs. Third Person
An autobiographer tells portions of his own life, using first-person narrative with pronouns such as "I," "me" and "we," while biographies retell stories in the third-person voice with pronouns like "he," "she" and "they." The language and atmosphere of the works are dramatically different. The autobiography creates a personal, intimate connection with the reader, since the writing comes from the subject's own point of view and language. Readers sense the persona of the actual author because he speaks to the reader in his own language, capturing part of the time period and region. The biography lacks the intimacy of reading the author's own words because you do not enter his mind as extensively. In a biography, however, you receive small pieces of the subject's voice since the biography author uses journals and memoirs as sources.
Subjectivity vs. Objectivity
In an autobiography, the subject is the writer and narrator, so the details are all through his eyes. This is called subjectivity, meaning that the message has a personal bias. You cannot completely trust a subjective author to be truthful or accurate in his story. A biography, however, is written based upon extensive research and a huge number of sources, giving the work more objectivity. Biographers gather all sources possible and include journals of the individual, diaries of people who knew him, newspapers, other books and every trace of history that remains. This provides more objectivity because the information comes from many independent sources.
Intimate Connection vs. Multiple Points of View
Since an autobiographer writes from his own mind, language and memories, you are able to connect with him and his words, feeling as if he is actually speaking to you. This can also be a flaw, since you only see his life from one angle, and the way the subject sees himself may be far different from the way others see him. One advantage of reading a biography is that it uses as many points of view as possible to give you a more complete picture of the individual, time period, friends, culture, world view and social history.
Examples of Both Texts
John Adams wrote narrative autobiographies of himself, and you can understand how he viewed himself, his world, the era of the Revolution and his presidency. Also, many authors have written biographies of Adams. For example, David McCullough's 2001 Pulitzer Prize winning "John Adams" represents a model of biographies, using extensive historical research and incorporating multiple viewpoints and sources.
Ben Franklin is also famous for his autobiographies, which are extensive and detailed. However, many people have read Walter Isaacson's 2004 biography "Benjamin Franklin: An American Life." Scholars doubt the truthfulness and accuracy of Franklin's own narrative autobiography. Despite this, both are useful to explore Franklin's life and time period, together creating a more complete picture of this Founding Father.