The legacy of BASIC on our industry can hardly be understated. The language and its mission at Dartmouth was innovative.
BASIC had immeasurable secondary effects simply by being the first programming language so many new computer users were exposed to (particularly near the dawn of personal computers).
Edit: I got sucked into some nostalgia.
Here's the 1964 edition of the Dartmouth BASIC reference: http://web.archive.org/web/20120716185629/http://www.bitsave...
It's really charming, and I think it gives you a bit of the feel for the time.
(I also particularly like, on page 21, the statement "TYPING IS NO SUBSTITUTE FOR THINKING".)