It's billed as a memoir of D-Day, but really it's broader than that. Lambert gives you an overview of his younger days, talks about enlisting before the U.S. entrance to World War II, then gives you the whole run-down of his service, right through D-Day. Then he goes on to talk about his recovery from the war and a little taste of what life was like after. It's written in a plain, unpretentious manner. Mostly Lambert explains any military jargon as he goes. It's really more of a personal account than a military history, so it is not consumed with strategy or tactics or even a blow-by-blow description of battle, except as it was directly experienced by Lambert. Sometimes he gives a picture of what else was happening in the war, relying on other accounts for that context. To the aficionado, some of these broader points might bear disputing, but remember that the value of this book is Lambert's own account of what he experienced. Anyway, Lambert notes that "the more information you get" sometimes "obscures rather than illuminates the truth" (p 128), so he knew well the problem of differing accounts.
One thing that interested me personally was seeing how cyclical some things were. Lambert talks about they would place a priority on stopping "bleeding; usually with a tourniquet...There are complications from using tourniquets, however, and the practice has greatly declined since my war." (p 26). In fact, after 9/11, the use of tourniquets went way back up among those deploying, and the "complications" were deemed much more manageable than thought in the period just before. When I first joined the Air Force in 1991, they taught that putting a tourniquet on someone was a sentence to amputate and warned against using them unless it was life-or-death. Yet once real combat went up after 9/11, the tourniquet was almost the first thing people reached for. So I guess some things come and go with war or peace.
Lambert's coauthor DeFelice noted the reason Lambert went on record with his account was the realization that few of his number were left, and, "as direct memory of a thing is lost, too often the lessons that it taught are lost as well." (p 240). Well spoken and all too true. So do your part, save part of the lessons learned, show some interest in history, read accounts like Lambert's. It's not the greatest or most sublime account of World War II ever written, but it's readable, accessible, and contains more than a few gems throughout. A good read.