The list author says: "A safety razor is a razor where the skin is protected from all but the very edge of the blade.These razors eliminate the possibility of a user being seriously injured by the blade, as is possible with a straight razor.
The first safety razor was invented in the late 18th century by a Frenchman, Jean-Jacques Perret, who was inspired by the joiner's plane. As an expert on the subject, he also wrote a book called Pogonotomy or the Art of Learning to Shave Oneself. In the late 1820s, a similar razor was made in Sheffield, England, and from the 1870s, a single-edge blade, mounted on a hoe-shaped handle, was available in Britain and Germany. One of the rarest European razors was made by "Comfort" and, while this was not a true safety razor, it remains a landmark in razor design. None of these razors are considered to be a true safety razor.
Described as a razor where "a small blade is held in a suitable frame and provided with a guard to prevent the edge of the razor from cutting into the skin", the first American safety razor was patented in 1880 by the Kampfe Brothers. The new razor featured a wire skin-guard along the razorís edge. Only one side of the actual blade is used to shave, and it must be removed often for sharpening.
Until the early 1970s, most safety razors were manufactured to accept a single, disposable razor blade. These blades were manufactured with either one or two sharpened edges, depending upon the design of the razor. This style of razor is no longer manufactured in the United States and is instead made by a number of companies such as Merkur of Germany, Treet of Pakistan, Weishi of China, and Parker of India. The blades are still being made today in a wide variety of countries including the USA, Israel, Russia, Korea, Japan, and Egypt. Some of the brand names include Merkur, Feather, Racer, Bigben, Lord, Treet and Bic."