There are many types of local posts and cinderella stamps. Here is an attempt to clarify them.
1. LOCAL POSTS - five types.
a) PUBLIC, local delivery - Local stamps are used to prepay the delivery of mail within a city, island or region. Sometimes they prepay express mail (same day or overnight service). Only the local stamps are used and the mail is delivered by the Local Post's employees and does not go through the national Post Office system. Examples - Many 19th Century Local Posts, Hawai'i Post, Lord Howe Island Courier Post .These are genuine local posts as they provide a real service and the stamps and covers are very collectable.
b) PUBLIC, national or international delivery - Local stamps are used to pay for the transport of mail from an island or place (that has no branch of the national Post Office) to the nearest branch of the national Post Office or to the nearest Post Office in another country. National stamps are also attached so that the mail can be delivered by the national Post Office system or internationally. Local stamps in the past were often attached to the back of an envelope, nowadays they are usually attached to the left front (the law having been changed in the U.K. for example) - the top right front is usually reserved for national stamps. This kind of local post is available to the general public on the island or place. Examples - Christmas Island (Pacific Ocean), Herm, Hustadvika, Kaulbach Island, Rattlesnake Island, etc. These are genuine local posts as they provide a real need for a small population and the stamps and covers are very collectable.
c) PRIVATE - Local stamps are used to pay for the transport of mail from a place (that has no branch of the national Post Office) to the nearest branch of the national Post Office. This kind of local post is a private service, usually restricted to one person, family or business and not available to the general public. (Very often operated by an individual from their own home with local stamps placed on their outgoing mail). These kind of Local Posts are purely philatelic and done for the fun of it. Examples - Pineapple Post, Shrub Oak Local Post, etc.
d) RAILWAY (RAILROAD) POSTS - Railway (Railroad) stamps are used to transport mail from one railway (railroad) station to another along the railway (railroad) line. Also from one station to another station and then onto the nearest branch of the national Post Office, if national stamps are attached also. Examples - Snowdon Mountain Railway, Talyllyn Railway, etc. These railway (railroad) posts often provide a real service for the transportation of mail and the stamps and covers are very collectable.
e) AIRMAIL POSTS - Non-government airmail stamps are used to transport mail by plane from one place to another. Also they were often specially issued for an experimental or first flight. Examples - L'Aero Club Populaire de Nice et de la Riviera, Klondike Airways Ltd., etc. These airmail posts often provide a real service for the transportation of mail and the stamps and covers are very collectable.
All the official beetle stamps issued by local posts to provide a real service are listed by country.
2. CINDERELLAS - two types.
a) Real places.
These are often labels that look like stamps and used to advertise an actual place, event, charity, product or to make a political or religious statement and placed on envelopes together with the regular stamps of a nation. They are often called poster stamps. They do not prepay any local post. Examples - this label from Switzerland.
b) Fantasy places.
These are artistic creations made to look like stamps and with made-up names. These are also called "artistamps". Examples - Ailinglapalap,Bolt Post, Ittoqqoortoormit,Wotje. These are obviously not real postage stamps to anyone with even a little knowledge of stamp collecting and geography.
These labels look like stamps, but never claimed to be stamps.
3. BOGUS LOCAL POSTS.
These are dangerous because they look like real stamps from an actual country or place. Upon closer inspection however, they are bogus because the name of the place is real, but:
a) It has been changed slightly. e.g. Somaliland & Somalia etc.
b) The place is in some kind of turmoil (Russian republics in the Caucauses for example) where it is hard to find anyone in real authority who can attest to their validity or not. e.g. Abhkazia, Chechnya etc.
c) No genuine local post exists, as it is actually a very small uninhabited island or bunch of rocks. e.g. - Redonda, Steep Holm etc.
d) No genuine local post exists, even though it has a small population. e.g. these Scottish Islands.
e) No genuine local post exists, even though it claims to be a breakaway region of a country. e.g. Dagestan, Occusi Ambeno, Republik Maluku Selatan.
4. ILLEGAL STAMPS.
The Illegal Stamps were defined by the General Assembly of the WADP (World Association for the Development of Philately), in its second meeting (6th of Oct. 2000), as: Illegal issues for territories which are not entitled to issue stamps and false stamps produced by fraudsters in the name of an issuing authority with the intent to defraud collectors. Examples - typical examples are the Benin/Congo/Timor sets.
The U.P.U. (Universal Postal Union) fights these illegal issues and publishes regularly circulars about them. This is also the reason of the creation of the WNS, the numbering scheme for the authentic postage stamps of UPU members.
To know more details about this topic, please visit the pages: http://www.stampshows.com/local-post.html or http://www.bistamp.com for the countries of the former Soviet Union.