Digital short runs
Single prints and small runs¬†are usually produced by digital print.
There are two main technologies here: direct to lens print on UV machines and inkjet printing on photo paper that is later laminated to lens by hand.
The first method allows for producing from one to¬† hundreds of copies, the other one serves the purpose¬†of preparing single print only, so called "proof of concept".
Bear in mind that "proof of concept" doesn't show 100% final effect in litho printing. The effect and color are just approximate. In digital printing "proof of concept" is a 100% final effect.
Direct to lens method is used where the edition varies btw over a dozen and hundreds of invitations, postcards or similar prints, only then it is financially economical.
Inkjet print on photo paper method¬† and lamination to lens comes in play with proof of concept or some artistic prints. The disadvantage is¬† sensibility to mechanical¬†damage and humidity.