If you know how to shade a piece of paper with a hard lead pencil and the difference when using a soft lead pencil then this is a book to expand your abilities with the humble pencil. Don't be frightened by the author's finished examples - by using the info and applying a little perseverance and common sense, I have improved my sketches a lot - and there is plenty more to learn in the book.
The author gives lots of food for thought, using a variety of 'pencils', and covers how to produce textures as diverse as skin, cloth, glass, fur etc. The two composite demonstrations at the end use the textures learned earlier in the book - one is a still life and the other a cat on the prowl at night.