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.
Razor common form of shaving in developed countries. Although designed to have a more ergonomic shape at both the handle and head (including commonly a pivoted head which keeps the blades angled to the skin at a pre determined angle through the shaving motion) the concept is very similar to that of the double edge razor. However, here the entire head assembly (known as a cartridge) is removed and disposed of, not just the blade. Also, it is common for these cartridge heads to have multiple razor blades set into them, commonly between two and five blades. Disposable safety razors are