In art, Limited edition prints were originally done, sue to the nature of printing processes. In the early days of litho printing, the processes involved could only guarantee the same quality of print on one run of prints, usually a hundred or so.
This lead to valued work having a limited print run, and therefore becoming valuable to the discerning art collector. Having only a limited number of prints instantly makes them more of more value. Obviously this still holds true today. This is despite the fact that modern printing methods can now guarantee the quality of every print.
Most modern limited edition prints are now done using a Giclee printer, which is basically are very high quality inkjet printer. How do I recognise a limited edition print? Limited edition prints will have a number written in the blank space underneath the print (something like 2/100), where the number 2 is the edition number and the 100 is the total number of editions. This is usually written in pencil, by the artist, on the bottom left hand side. The artists signature (also in pencil) will be on the left hand side. Accompanying the print will also be a certificate of authenticity, which will also repeat these details, along with the publishers information.
How do I know if it's genuine?
If the print comes with the signature and certificate that's a good start. Most importantly, it's who you are buying it from. If you're buying from an established high street gallery, you should be fine. The real risk is buying online. You can research the online gallery to see if they have a premises and are a registered business. Again, if they are an established art dealer with a proper high street gallery you should be ok. If they are just somebody trading from home be a bit more careful. It is possible that you could be buying either a fake,or an imported edition, neither of which will have the value of what you think you are buying. The main thing to remember is that if in doubt, use an established gallery. There shouldn't be any prints that you can't get from these places.