When all the prints are created from the matrix (or master file) to be identical, this is called an "Edition". The artist generally limits the edition to a certain number of their choice. He or she then indicates in pencil (usually in the bottom left hand corner) the number of each individual piece and the total number of copies in the edition, for example, 5/40. Generally, once the printing of the whole edition is over, the artist destroys the matrix so that no additional prints can be made While the artist is the creator of the matrix, which is the fundamental part of the artwork in printmaking, it is not uncommon for the actual printing to be done by an editorial. However, the first few prints are made at least in the presence of the artist who can then make any necessary modifications or changes to the matrix. These prints are called the artist's proofs. Each one is considered a unique and one-of-a-kind artwork and has a higher commercial value than the rest of the edition. Generally they make up between 5 and 10 percent of the total edition number. Therefore the edition may be 100 and there are 10 artists proofs totalling 110 images all together. The proofs are marked with roman numerals, for example: II/V (second of the 5 total proofs).