I found this book to be very useful and full of information. For me the most helpful part was not only the angle of which to hold the blade at. For example using a wood chisel, but also how much pressure to put on it when sharpening it. That way you are not damaging the blade, but are able to get the wright amount of pressure for an equal sharpness around the entire chisel. You want to be able to use your tools multiple times and this book gives you that tool. You should not use a grinder all the time because eventually you will end up replacing the tool and that is no good especially if you have old tools like form your grandfather who worked with wood and you would like to continue to use those this is the book for you. The author shows you through pictures and diagrams how to sharpen all of the tools you would use on wood, form axes, saws, planes, drill bits, I just picked chisels because I have a lot and was able to use them easily. The drill bit section was also helpful as well. For me I found this to be a very helpful and useful book and I think anyone that works with wood would also find this book useful as well.