who invented lithography and what was its original purpose
Lithography (from Ancient Greek λίθος, lithos, meaning' stone', and γράφειν, graphein, meaning' to write') is a method of printing originally based on the immiscibility of oil and water. The printing is from a stone (lithographic limestone) or a metal plate with a ball grained surface. It was invented in 1796 by German author and actor Alois Senefelder as a cheap method of publishing theatrical works. Lithography can be used to print text or artwork onto paper or other suitable material.