The term safety razor refers to a shaving razor that has a protective guard between the sharp blade and your face.
Straight razors also called cutthroat razors were introduced in the 17th century. These razors required great skill to use and keep sharp.
By the 18th century inventors began fitting guards and handles to razor blades in an effort to make manual shaving easier. They were a lot safer but it still required skill and time to sharpen the blade.
The modern safety razor, with it's disposable blade, became popular in the early 1900's and were given to troops during World War I.
They remained popular until the 1970s when companies began embedding the razor blade in plastic and selling disposable and cartridge type razors.
These new plastic razors eliminated the need to ever touch a sharp razor blade but created large amounts of waste.
The double edge safety razor is a compromise between safety and waste creation. The razor itself will last a lifetime, but you do need to be a bit careful when you change the removable blade.
