It characterizes an original work( only one copy) made and signed by the artist who is free to use a large variety of techniques. These techniques generally fall into two categories :
Painting :usually oil and /or acrylic on canvas , gouache or watercolours on drawing paper ;
Monotype : a work of art made out of different materials and using various techniques (paint , thick pastel , ink , paper collage , material , …)
Whereas canvas is mostly and basically used , any other material has been nowadays experimented : wood , paper , metal , steel , nylon net , concrete…

WORKS WITH LIMITED EDITION 

Limited edition implies that each lithograph or engravement is edited in a restricted number of copies depending on the agreement set up between the publisher and the artist ; moreover , each copy must be signed by the artist himself which assures its exclusive rights. Slabs are destroyed immediately after edition.
The making of prints - images printed thanks to engraved or drawn materials (metal , wood or lithographic stone) – and engraving practice are closely linked to reproduction and distribution of other forms of art (painting notably ) and fully participate in art

• LITHOGRAPHY

Lithographic process was invented in 1798 in Germany by Senefelder ; it enables the artist to distribute an original work to a larger public.
The artist creates directly on the material , he draws his subject with a thick pencil or ink on a limestone previously sanded , grained and greased ( or nowadays on a grained zinc slab ).The stone is then coated with acid ( which enables colour to become fixed on the drawn part only) and made wet.
Printing on paper requires a hand-press.
To each colour of the lithograph corresponds a different stone , the sheet of paper moving from one stone to the other , one colour after the other.
Once the process is completed , the stones are destroyed or erased with an acid and each lithograph is numbered and signed with a black pencil by the artist

Engraving is a printing technique that dates back to the XVth century and uses an embossed matrix (metal slab).
The intaglio engraving (on brass slab) also called « soft cutting » uses the engravings made by different tools ( dry tack , burin , …).
Once engraved , the slab is inked then dried so that the ink only remains into the cuttings and afterwards ,
under strong pressure , it lays on a paper that was formerly made supple by humidification.
The resulting embossment can easily be identified by the presence of a basin (a hollow resulting from the pressure of metal slab on paper) .
The main engraving techniques are etching , dry tack , carborundum , aquatinte and black way.