If you want to learn to knit, or improve your knitting, I found that supplementing a book with videos helps immensely. There are a ton of videos online so that you can watch someone doing what you want to do (e.g. casting on, switching yarn color, etc) while using a book for reference so that you learn the technique and terms.
1. Big Book of Knitting by Katharina Buss, English Edition 1999 - a book I peruse
I've referenced this book multiple times during my on-and-off obsession with becoming a better knitter. This book contains the basics, including advanced concepts (i.e.stitches). Diagrams and pictures are included, but the instructions are not the clearest.
This may be because the original edition was in German and Americans need better instructions. Or, more importantly, for someone to point out what not to do and common errors when trying a new stitch.
Below are some lessons learned from my knitting ventures:
Ribbed Stitch - The book does not tell you this, but when you switch from a purl to knit stitch, you need to make sure the yarn is behind the lead needle. And, when you switch from a knit to a purl stitch, the yarn needs to be in front of the lead needed.
Blocking - When you knit, an item tends to curl in so Blocking an item basically means straightening or flattening an item so that it does not curl. Make sure that the item is thoroughly wet. I was afraid of ruining my item so would only halfheartedly dampen an item before blocking. (Caveat - if you use expensive yarns, which I do not, thoroughly wetting an item may ruin an item, so check the label.)
My cousin Christina uses pin to pin the wet item flat and leaves it overnight until the item drives. And voila - straightened item! Or, so she says since this has never worked for me...
I forgo the pins - partly because I am impatient and only know how to knit scarves, so that's a lot of pinning that I need to do. So instead, I steam block and flatten a section of my scarf, put a pillowcase over it, wet the pillowcase pretty thoroughly with a spray bottle, and then iron over the pillowcase steaming the item underneath the pillow case.