I wrote the first edition of the book in late 2017 and 2018, and I’ve spent the last year updating it for 2022. Rather than being thankless drudgery, re-writing a book is actually way more fun than I expected. One of the most enjoyable parts of producing this book has always been asking myself questions like “Why do you think that?” and “If we go back to first principles, why does it work better for users this way?” - and re-approaching all 101 principles fresh after a few years has made me re-evaluate a lot of my thinking. This time I’ve been asking myself “Do I still think this?” and “How could this be better for users?”. The fundamentals are of course unchanged - but how we deliver these experiences to users has been sharpened and refined. Over 80% of the content has been tweaked, or fully rewritten - with new chapters, illustrations, more examples and code snippets and clearer explanations of key points. There’s more content about working in enterprises (not just startups and consumer products), more focus on responsive design and accessibility - and more advice about real-world implementation of the principles. If you do decide to buy the book, thank you - and I hope you enjoy reading and get a great deal of value from it.