Readers know well how much we Maggie's Farmers thrive on the Teaching Company series, but this is a welcome addition to our self-education arsenal: The Very Short Introductions series from the Oxford Univ. Press.
Their "very short" paperbacks on all sorts of topics are elegantly-written and will leave you as well-informed as a kid taking a college course.
I perused two of them, one on The Cell and one on Christianity. Excellent. Most can be gotten on Amazon.
I'll begin with this one: The History of Medicine: A Very Short Introduction