Razor be used on both sides, with two open edges. The blade on the double-edged safety razor is slightly curved to allow for a smoother and cleaner shave. In 1901, the American inventor King Camp Gillette, with the assistance of William Nickerson, patented a new variation of safety razor with disposable blades. Gillette realized that a profit could be made by selling an inexpensive razor with disposable blades. This has been called the razor and blades business model, and has become a very common practice for a wide variety of products. Many other brands of safety razors have come and gone.
Safety razor was one of the first improvements made to guard razors. The basic form of a razor, "the cutting blade of which is at right angles with the handle, and resembles somewhat the form of a common hoe", was first described in a patent application in 1847 by William S. Henson. This also covered a "comb tooth guard or protector" which could be attached both to the hoe form and to a conventional straight razor. The first attested use of the term "safety razor" is in a patent application for "new and useful improvements in Safety-Razors", filed in May 1880 by