With Hidato's you are given a grid of squares with some numbers already filled in. The idea of the puzzles is to join all the numbers in sequence - as you would expect in each case there is only one unique logical solution.
You get 200 puzzles for your money. I am gradually working through the book, the puzzles gradually increase in size and difficulty. There is only a small introductory segment giving advice on strategies to solve the puzzles, but this doesn't matter, you will be able to work out your own.
The book is sturdy and has a good, clear lay out.
All in all, thoroughly recommended to puzzlers.