During Daniel's varied and interesting career, he produced thousands of articles and numerous books as a war correspondent, photojournalist, investigative journalist, book and music critic, features writer, columnist, and technology reviewer and analyst. His work appeared in scores of magazines, newspapers and journals.
A member of the National Book Critics Circle, The Authors Guild, Science Fiction and Fantasy Writers of America, the Overseas Press Club, and the American Society of Journalist and Authors, Daniel was a frequent speaker at conferences and other events on writing, literary criticism and the publishing industry.
Daniel's books were as varied as his reporting and his multifaceted mind.

In addition to his renowned biography of J.R.R. Tolkien, Daniel wrote seven other non-fiction books (co-authored with his wife Sally Wiener Grotta, including Digital Imaging for Visual Artists (McGraw-Hill), the first major book about the (then) new field of imaging and digital photography. Other non-fiction books include The Green Travel Sourcebook, The Illustrated Digital Imaging Dictionary, PC Magazine's Guide to Digital Photography and others.
Daniel's fiction includes Seven from Haven (a short story collection), the novella Honor, and Adam V (a novel he completed just before his death), plus short stories.
Daniel's J.R.R. Tolkien: Architect of Middle Earth was the first biography of the creator of The Lord of the Rings and The Hobbit. It was in print continuously for 30 years, was translated into numerous languages around the world, and once had the dubious honor of being the most stolen library book. (As a result, a special library edition was published.)
In a reversal of the usual publishing timeline, it was originally published as a mass paperback, then as a trade paperback, and finally as a hardbound book. This was taken by the publishing industry as an indication of a book that was underestimated by the initial publisher, and which rose on its own to a higher market level.
For well over a decade, Daniel Grotta and Sally Wiener Grotta were PC Magazine's resident experts on digital photography, imaging, scanning, color management and anything else related to pictures in computers. At PC Magazine Labs, they created the test scripts for digital photography, cross-platform testing, imaging software, scanners and digital image quality, as well as defined many of the magazine's other protocols and procedures for testing and analyzing various imaging products and processes.
Daniel and Sally wrote well over 1,000 articles and reviews on technology for just about all the major tech publications, as well as numerous books on imaging and photography. Team Grotta, as they were known, were also popular speakers on imaging and photography, having conducted seminars throughout the continent, and appearing on various TV and radio shows.
At DigitalBenchmarks, the Grottas expanded and extended the test processes and protocols that they established at PC Magazine Labs, to provide greater in-depth competitive analyses, R&D testing, market analyses and other services. Their clients ranged from manufacturers to investment companies to corporate users of digital technology.
Sally Wiener Grotta continues to lead the team at DigitalBenchmarks.