From Booklist

When writers look at the birth of the computer age, they generally focus on the tangible hardware achievements of the likes of IBM and Intel and almost solely on Microsoft when it comes to software. Campbell-Kelly tells us that in the larger perspective, Microsoft is not the center of the software universe and indeed today makes up only about 10 percent of that industry. Mass-market “shrink-wrap” software is the retail version of a much larger sector that contributes to our lives constantly, running everything from airline reservations to bank transfers, credit-card transactions, and most corporate and government functions, including the space program. This is an area that is often ignored because software is hard to define; it is the nearest product we have that is virtually pure thought.

Campbell-Kelly is the first historian to give us a comprehensive overview of this hidden industry, which spawned the first user groups when companies had to write their own programs for early IBM mainframes. He includes everything from the information infrastructure of IBM’s CICS and SAP’s R/3 to the ever-popular gaming software. David Siegfried