https://www.youtube.com/watch?v=f_uwKZIAeM0&t=1s (Intro to machine learning - 2 minutes)
Vector basics: https://www.geeksforgeeks.org/data-science/vectors-for-ml/ (Short blog post, just the beginning half is sufficient for our next session)
The book chapter https://web.stanford.edu/~jurafsky/slp3/5.pdf OR related slides https://web.stanford.edu/~jurafsky/slp3/slides/vector25aug.pdf. The slides may be quicker to review