Nordisk Familjeboks Sportlexikon is a very big book that has lots of information about different sports. It's like a big encyclopedia for sports. Like how we have a big book with information about all the animals in the world, this book has information about all the sports people play in the world. This book is made for people who love sports and want to learn more about them. So, if you are curious about a sport, you can look it up in the book and find out all the information about it. People find this book very helpful because it has a lot of information about different kinds of sports, how to play them, and the history behind them. But remember, it's a very big book, so it might take some time to read all the pages.