On this day in 1906, Nobel laureate George David Wald was born. Dr. Wald, a renowned neurobiologist, is best known for his study of the retina. For more on his life, click here.

On this day in 1950, Robert Holbrook Smith, a.k.a. "Dr. Bob", the co-founder of Alcoholics Anonymous died of colon cancer. During his career, he helped thousands of  recovering alcoholics. Read more about him here.

Today is the birthday of Sir Frederick Grant Banting, the physician who pioneered the use of insulin to treat diabetes in humans. For more on his life and work, check out this article.