How well we read is determined both by our eyes and our brains. We are more likely to read quickly and understand what we read if our brain is properly set up to absorb whatever information will be coming our way. Preparing our brains to absorb information is known as priming.
You are probably already familiar with this. If you have a favourite book and you re-read it, you will be able to read it much more quickly and take more in the second, third or fourth time around because you already know what is coming. Although you probably won’t remember everything when you sit down to read it again, you will remember enough to ensure that you get more out of it on subsequent occasions.
If you are reading a new book you can prime yourself in a number of ways. If it is reading for work or a project you can write down what your aims are. This will help you notice what is important as you read. If you have some knowledge of the subject, you can brainstorm that knowledge beforehand noting down everything you already know. This will set up hooks for you to attach new information to. You can also flick through the book at a page a second. This will give you a quick preview of what is coming your way.