An introduction
On a previous page I've explained the first criteria a genuine 'original print' should satisfy.
The second criteria I'll explain by quoting a reputable and renown specialist in 'original prints': StJudes Prints. "At it’s simplest, we define an original print as an artwork that has been manually printed by the artist…" Source: "What is an original artist's print?" http://stjudesprints.co.uk [ Accessed: Mar '16 ]
There are three types of print (Giclée, Lithographic and Original) that you're likely to encounter and unfortunately they are not always labelled correctly. So I've identified which are machine printed so would not satisfy StJudes criteria/definition of an 'original print'.
Machine made – Giclée and Lithograph
Giclée prints and Lithographic prints are always printed using (large format) printing machines. The whole printing process is handled by the printing machine once the 'print' button has been pressed.
The artist might have to change a roll of paper or an ink cartridge, but beyond this, there is minimal involvement with the machine which will happily complete prints alone, while the artist is elsewhere, doing other things.
Giclée prints
Giclée prints make use of inkjet technology and special print machine-friendly giclée inks which are resistent to fading. In Giclée printing, all the colours are applied at the same time, much like your home printer prints. It's perfectly practical to print one print in an edition, with a long gap before printing another so keeping track of giclée editions does take discipline to ensure numbering is correct.
Despite being machine printed, it is claimed that giclée prints can last between 70 and 200 years before degrading, depending on their care during this time of course*.
Lithographic prints
Lithographic prints (sometimes called offset litho, lithoprints or simply litho) are the older technology of these two. It predates computers, though modern day lithographic printing machines do now use computer technology. Four colours are printed individually, one on top of another, to create the image. Lithographic printing isn't used to print just one as it's simply not practical. This is why national privately owned gallery chains and publishers of fine art prints tend to use Lithoprint because they're printing editions of 100+.
The maximum life of a lithograph is supposed to be 30 years before it begins to fade/yellow*.
Hand made – Original Prints (including handmade lithographs!)
There are lots of ways to make original prints and all of them involve a lot of manual or 'by-hand' work.
The list of what the original printmaker does manually varies according to the method they're using to make the prints. At the very least there is a manual creation of the printing plate or block. The work a printmaker does by hand can include: carving a printing block, mixing the inks and inking the block using a roller. They'll often lay the inked block with its paper on the press and then turn the press by hand. An artist will repeat the activities just listed however many times is necessary to build up the colours of the print and for each and every print in the edition.
There's a whole host of variations, but original prints, as StJudes say, are artworks manually printed by the artist. The list of ways in which an original print can be made are many and highly varied. Linoprints/cuts, woodcuts or wood engravings (they are similar but distinctly different), collagraph, monotype/prints and etching is not a complete list but covers most of the types of original print you're likely to encounter.
Confusingly, lithograph should be in the list – but only a special kind of lithograph where the artist has worked directly onto the plates. The vast majority of lithoprints are not original prints.