“Understanding Quantum Technologies” is a book I created first in 2018 and updated every year in September since then. I switched the book language from French to English in the 2021 edition.

It is a comprehensible book covering everything you’d like to know when discovering the quantum ecosystem, or even getting updates on it. It covers the history of quantum physics and its fundamentals, quantum information science, quantum computing hardware including enabling technologies, quantum algorithms, software tools and applications, quantum communications and cryptography, quantum sensing and quantum worldwide ecosystems.

The book is free to download in PDF and available in paperback version on Amazon. Since the 2021 edition, there are multiple versions of the PDF, with all the book in a single PDF, or split in several parts to accommodate the memory limitations of ebook readers. There are also A4 as well as Letter versions available. Since the 2023 edition, I also publish a short version of the book, with 38 pages for the 2025 edition. You can click on the image below to directly download the A4 version of the 2025 edition.

Here are the links to the posts describing the various editions of this book from the newest one to the older one, with all the download links:

• Understanding Quantum Technologies 2025, September 2025 (1,524 pages) and on the Amazon paperback version.
• Understanding Quantum Technologies 2024, September 2024 (1,554 pages).
• Understanding Quantum Technologies 2023, September 2023 (1,366 pages).
• Understanding Quantum Technologies 2022, September 2022 (1,184 pages).
• Understanding Quantum Technologies 2021, September 2021 (884 pages).
• Comprendre l’informatique quantique 2020, Septembre 2020 (664 pages), the last one in French.