While visual media are quite diverse, one of the most important turning points came with the invention of the printing press.
  A true revolutionary creation, it opened up a whole new medium in the form of relief prints.
For the first time, an artist was able to carve an image onto wooden or metal blocks, ink the block and impress it on paper.
Furthermore, relief printing created the first kind of reproducible art.
The action of carving an image has its own challenges and the first results were quite unlike any other traditional techniques used until that moment.
For instance, there is an intrinsic difficulty in reversing the image on the printing plate and it is a complex skill that requires great patience.
  The method of inking and printing on paper also requires significant dexterity and knowledge of a lengthy process with multiple steps.
In attempting to perfect his ability to engrave reverse images on copper plates, Alois Senefelder began practicing on cheaper slabs of Bavarian limestone.
In addition to introducing the use of the limestone slab, Senefelder concocted a mixture of wax, soap, lamp black and rainwater that he used as a correction fluid on the copper plates.
Experimentation and a dose of serendipity brought together these two main elements specific to lithography.
Senefelder realized that the use of his correction fluid on the limestone created a surface resistant to water.
Oil based ink would not adhere to the wet stone.
The basic concept on which lithography is based had been formulated.
  Senefelder proceeded to patent his printing method in 1799.
The appearance of stone lithography was the first printmaking technology that allowed the traditional artist to work using more familiar methods.
Through lithography the artist could create prints that could rival an original painting in attaining exquisite detail, mood and color variations.
It became exceedingly popular as a medium by the 1830s and it was widely used to create illustrations for books, as well as flyers and posters.
It is still used today by artists all over the world.
The appearance of stone lithography changed the notion of printmaking in a radical way.
  Naturally, the steps involved in Senefelder's original litho printing process have been subject of innovation over the years.
In time, they became the modern offset lithographic printing so popular today.
Yet many artists still feel that Senefelder's traditional method allows for the artist's creative expression to really shine through.
The original process is such that it incorporates individual and distinctive features into every single print.
In essence, the images can never be truly replicated and each print is an original unto itself.