John Walkenbach is a prolific and bestselling Microsoft Excel author. He has written over 50 books about Excel, including books on VBA, formulas, and the bestselling Excel Bible series. John also runs the website spreadsheetpage.com, one of the longest running Excel sites around (est. 1996). His website has tips, books, a categorized list of Excel resources, and a blog. John has a clear and direct writing style, and an excellent sense of humor.