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 highly similar in design to Cartridge Razors, constructed from inexpensive materials (commonly injection moulded polycarbonate), yet are meant to be wholly disposable after use with no blade sharpening or replacement possible. One device was invented in 1963 by American entertainer and inventor Paul Winchell. Safety razor life may be extended by drying the blades after use. The electric razor (also known as the electric dry shaver) has a rotating or oscillating blade. The electric razor usually does not require the use of shaving cream, soap, or water. The razor may be powered by a small DC motor, which is either