I won this book in a First Reads contest.
I am very impressed with this Excel book. In all of the books that I have read about Microsoft Excel, I have never seen such a clear, detailed guide about the use of arrays in Excel.
In the beginning of the book, Mike Girvin lists and summarizes the prior knowledge that is required to understand this book. The author, who has many videos tutorials about Excel online, describes array formulas in such a way that anybody who has this prior knowledge can understand (and begin to master) them.
This book has a few strong points. One strong point is that each chapter has a large number of examples that the reader can follow. The examples include a large number of images, and readers can download the examples' spreadsheets from the author's website. The second strong point is that, especially in the earlier chapters, when an example contains a long (and somewhat confusing) formula, the author will review that formula, step by step, at the end of the example. A third strong point is that, in the end of many chapters, the author compares formulas, showing which formulas perform fastest on large sets of data. Finally, the author includes formulas from different versions of Excel, so that readers who do not have the latest versions of Excel can still benefit from reading this book.
In the introduction to the book, the author writes that he believes that he has done a "less than stellar job" writing the book. I think that the book is very clear, but the book could have used more proofreading. There were many typos, which I occasionally found to be very distracting. However, the clarity of this book more than makes up for the typos, and I recommend this book for anybody who needs to deal with large sets of data in Microsoft Excel.