Want to learn to meditate? Read this book. This is the only book you need. Promise. It's free, too.

It is written by a secular monk who has a tremendous appreciation for and understanding of neuroscience as it relates to the practices. You don't need to be a Buddhist to go deep with the techniques in this book.

One of the other things I like about it is our author incorporates contemplative practices spanning many cultures and timeframes, including medieval Christianity—which, surprisingly, was independently onto something quite in line with the teachings of the Buddha—with practices that have been lost to us over the centuries yet remain (potentially) enormously empowering.