Depends on your mode of learning but I've had more success with a couple of months of Lynda.com than any book I ever bought. There are cheaper yearly alternatives but you can get a monthly premium subscription for $40. you will learn more with 2 4 hour courses that any book out there. They are really strong with Lightroom 7 Photoshop. Can't recommend this highly enough. After teh 2 days it will take you to master lightroom there are tons of general and specific photography courses.