I have a slightly odd hobby. I really enjoy stamp collecting. 
Cool, you can also say you're into philately (a word for the study of stamps).
Oh I didn't realize it had an actual name. That's awesome. Do you know when stamps first started being used?
Well the word is derived from a French word and coined in 1864, so that far back at least. Probably a lot longer since mail has been around a while.
Yeah for sure. I'm trying to get a good collection of old and new. Do you know anything about the most expensive stamp ever?
There is a stamp called Inverted Jenny which is an error where an airplane is printed upside down. A single one was sold for $977,500.
Wow! I don't think I will ever be able to afford anything quite like that hah! Is that the most unique stamp out there?
Invert error
In philately, an invert error occurs when part of a postage stamp is printed upside-down. Inverts are perhaps the most spectacular of postage stamp errors, not only because of their striking visual appearance, but because some are quite rare, and highly valued by stamp collectors.
Characteristics.
Invert errors, or "inverts" for short, most commonly arise when producing multi-colored stamps via multiple passes through the printing press. It is all too easy for a printing plant worker to insert a
Philately
Philately (; ) is the study of stamps and postal history and other related items. It also refers to the collection, appreciation and research activities on stamps and other philatelic products. Philately involves more than just stamp collecting, which does not necessarily involve the study of stamps. It is possible to be a philatelist without owning any stamps. For instance, the stamps being studied may be very rare or reside only in museums.
Etymology.
The word "philately" is the English translation of the French "