I honestly never thought I would write a book so soon in my life. When the MongoDB Data Modeling project was presented to me, I embraced this challenge and I have always believed that it was possible to do. However, to be able to start and accomplish this project would not have been possible without the help of the Acquisition Editor, Hemal Desai and the Content Development Editor, Merwyn D'Souza. In addition, I would like to thank the Project Coordinator, Judie Jose, who understood all my delayed deliveries of the Arduino Development Cookbook reviews, written in parallel with this book.

Firstly, I would like to mention the Moutinho family, who were very important in the development of this project. Roberto Moutinho, for your support and for opening this door for me. Renata Moutinho, for your patience, friendship, and kindness, from the first to the last chapter; you guided me and developed my writing skills in this universal language that is not my mother tongue. Thank you very much Renata.

I would like to thank my teachers for their unique contributions in my education that improved my knowledge. This book is also for all Brazilians. I am very proud to be born in Brazil.

During the development of this book, I had to distance myself a little bit from my friends and family. Therefore, I want to apologize to everyone.

Mom and Dad, thank you for your support and the opportunities given to me. Your unconditional love made me the man that I am. A man that believes he is able to achieve his objectives in life. Rafaela, Marcelo, Igor, and Natália, you inspire me, make me happy, and make me feel like the luckiest brother on Earth. Lucilla, Maria, Wilson, and Nilton, thanks for this huge and wonderful family. Cado, wherever you are, you are part of this too.

And, of course, I could not forget to thank my wife, Christiane. She supported me during the whole project, and understood every time we stayed at home instead of going out together or when I went to bed too late. She not only proofread but also helped me a lot with the translations of each chapter before I submitted them to Packt Publishing. Chris, thanks for standing beside me. My life began at the moment I met you. I love you.