In numismatics, an error refers to a coin or medal that has a minting mistake, similar to errors found in philately.

The Inverted Jenny ( also known as an Upside Down Jenny or Jenny Invert ) is a United States postage stamp first issued on May 10, 1918 in which the image of the Curtiss JN-4 airplane in the center of the design appears upside-down ; it is probably the most famous error in American philately.

Only one pane of 100 of the invert stamps was ever found, making this error one of the most prized in all philately.

Whereas philately is concerned with the study of the stamps per se, including the technical aspects of stamp production and distribution, philatelic postal history refers to stamps as historical documents ; similarly re postmarks, postcards, envelopes and the letters they contain.

Socked on the nose (" SON "), also called Bullseye, in philately, refers to a cancellation of a postage stamp in which the postmark, typically a circle with the date and town name where mailed, has been applied centered on the stamp.

The term philately is derived from Greek wordphiloteleia '- philos referring to love of things and ' telos ' referring to a tax. Mr. Herpin is the the originator of the term ' philoteleia. Before the Greek term ' philoteleia ' was coined the hobby was called ' Timbromaine ' or ' Timbrology ',' Timbre ' in french refers to stamp.

* Socked on the nose in philately, refers to a certain type of cancellation of a postage stamp

The study of postage stamps and their use is referred to as philately.

Philatelic literature is written material relating to philately, primarily information about postage stamps and postal history.

In philately, a mixed franking is an occurrence of postage stamps of more than one country or issuing entity on a single cover — or the occurrence of postage stamps of more than one currency of a country or issuing identity on a single cover.

In philately, private overprints are overprints ( pictures, text, or a combination of the two ), usually rubberstamped though occasionally applied by some other method, to postage stamps ( or, occasionally, postal stationery ) used by some person or entity other than a government or other official stamp-issuing entity.

In philately, a block is a group of postage stamps still attached to each other.

In philately, a pen cancel is a cancellation of a postage or revenue stamp by the use of a pen, marker or crayon.

In philately, a cachet is a printed or stamped design or inscription, other than a cancellation or pre-printed postage, on an envelope, postcard, or postal card to commemorate a postal or philatelic event.

The term Zemstvo stamp is also used in philately to refer to local-issue Russian postage stamps from this period.

In philately, a cinderella stamp has been defined as " Virtually anything resembling a postage stamp, but not issued for postal purposes by a government postal administration ..." The term also excludes imprinted stamps on postal stationery.

In philately, " errors, freaks, and oddities " or " EFO " is a blanket term referring to all the kinds of things that can go wrong when producing postage stamps.

* Gutter ( philately ), the space between panes of postage stamps that creates configurations of " gutter pairs " or " gutter blocks ".

In philately, the term cover pertains to the outside of an envelope or package with an address, typically with postage stamps that have been cancelled and is a term generally used among stamp and postal history collectors.

A line pair in philately is a coil pair of postage stamps bearing an inked line between the two stamps.

* Earliest known use, a philately term usually referring to the first day of issue of a postage stamp or postmark

* bisect ( philately ), the use of postage stamp halves

A digital stamp, in mail or philately, is similar to a conventional postage stamp except it is resident on or in a computer.

In philately, a Silver Jubilee issue is an issue of postage stamps by the British Post Office and the Post Offices of Commonwealth countries and British dependencies to commemorate the monarch's twenty-fifth anniversary on the throne.

In philately, a Coronation issue is an issue of postage stamps made by the British Post Office and the Post Offices of Commonwealth countries and British dependencies to celebrate the coronation of a new monarch.

This mint stamp of the 1918 Russian revolution era is much less commonly found used. A mint high value 100 Rupee key type stamp of Ceylon valid for postage or revenue use and vulnerable to tampering to remove a fiscal cancel to make it appear to be a more valuable unused stamp. In philately, a mint stamp is a stamp which is in its original state of issue, is unused, has never been mounted and has full gum, if issued with gum.

In philately a reprint is a new printing of a postage stamp from the original plates.

The colors of postage stamps are at once obvious, and among the most difficult areas of philately.

The origins of philately lie in the observation that in a number of apparently similar stamps, closer examination may reveal differences in the printed design, paper, watermark, colour, perforations and other areas of the stamp.

Traditional philately is the study of the technical aspects of stamp production and stamp identification, including:

In philately, the watermark is a key feature of a stamp, and often constitutes the difference between a common and a rare stamp.

* Killer ( philately ), term for a heavy stamp cancellation mark

The term " surcharge " in philately describes any type of overprint that alters the price of a stamp.

In philately, gum is the substance applied to the back of a stamp to enable it to adhere to a letter or other mailed item.

1850 3Kr red stamp Se-tenant_ ( philately ) | se-tenant with St. Andrew's cross ( philately ) | St. Andrew's cross label

* Variety ( philately ), a term in stamp collecting

The American Philatelic Society ( APS ) is the largest nonprofit stamp collecting and organization of philately in the world, with almost 44, 000 members from 110 countries.

* Easter seals ( philately ) Easter seals in stamp collecting.

This 1932 Canadian " first official flight " cover, Great Bear Lake to Rae, includes both a special cachet and a surcharged airmail stamp. Aerophilately is the branch of philately that specializes in the study of airmail.

Only a few examples survive in private hands, making this stamp one of the great rarities of British philately.

The stamp catalog is an essential tool of philately and stamp collecting.