From his work on the Manhattan Project to the key role he played in explaining the Space Shuttle Challenger disaster, Richard Feynman (1918-1988) is known for many things. But to generations of students, the late physicist is perhaps best known as the brain behind The Feynman Lectures On Physics.
A quick look at Amazon.com shows that a new copy of the text can be had for $332.95. But you don't have to spend a dime, now that Caltech has created a free online edition of the Lectures.
The online edition features all the familiar lectures, including those the Nobel Prize-winning physicist delivered on matter, electromagnetism, and quantum mechanics. The material can be read on all sorts of devices, according to the website, and everything can be "zoomed without degradation."
So have a look. But unless you're a whiz, don't expect to understand all of Feynman's physics. As Feynman himself once said, "Hell, if I could explain it to the average person, it wouldn't have been worth the Nobel Prize."