A polyhedron (plural polyhedra or polyhedrons) is often defined as a geometric object with flat faces and straight edges (the word polyhedron comes from the Classical Greek ÏÎ¿Î»ÏÎµÎ´ÏÎ¿Î½, from poly- , stem of ÏÎ¿Î»ÏÏ, many, + -edron, form of ÎµÎ´ÏÎ¿Î½, base, seat, or face). polyhedron is any three-dimensional figure with flat surfaces that are polygons. Specifically, any geometric shape existing in three-dimensions and having flat faces, each existing in two-dimensions, which intersect at straight, linear edges.
In 1839, Charles Goodyear invented rubber vulcanization, but the first rubber condom was not produced until 1855. Just a few short years later, the majority of rubber companies were producing condoms as well. These condoms were reusable, which meant they were much more affordable.
Condoms have been made from a variety of materials; prior to the 19th century, chemically treated linen and animal tissue (intestine or bladder) are the best documented varieties. Rubber condoms gained popularity in the mid-19th century, and in the early 20th century major advances were made in manufacturing techniques.Prior to the introduction of the combined oral contraceptive pill, condoms were the most popular birth control method in the Western world.he rubber vulcanization process was invented by Charles Goodyear in 1839, and patented in 1844. The first rubber condom was produced in 1855, and by the late 1850s several major rubber companies were mass-producing, among other items, rubber condoms.