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Telephone cards have been in use since 1978 when Italy, one of the first countries to adopt this form of payment, began changing the machines that functioned via money and cards. One of the arguments used to justify changing the traditional phone cabins for newer card-using ones was the reduction in the destruction of public cabins to steal the coins inside. Other reasons included the reduction in employees needed to collect the coins and lower maintenance costs due to fewer mobile or mechanical parts.

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Most of the world's telephone cabins now use card-based systems, which means operators launch hundreds of different card designs a year to satisfy user demand. This fact alone has helped to convert telephone cards into highly collectible items.

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As in most collectible objects, it is the collectors themselves who tend to impose their own criteria when it comes to selecting the objects. However, one of the most common is the year of issue, which means the collection can run from the late 1970s right up to the present day. Although there are other criteria:

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- Country of origin of the card. It is not necessary to travel to the country in question to find them as many can be purchased in markets, fairs and, of course, over the internet, the largest market for collectors of all types. The most common way of finding them, however, is for the collector, friends or family to visit the country of origin.

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- Themes. The variety of themes is currently huge. Some of the most common are: planes, boats, cars, Disney, fauna, tobacco, trains, cars, natural parks...

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- Technology used. This is possibly the most common criteria as it is the most challenging for collectors. There are three main types of technology:

a) Magnetic cards. Although there are several manufacturers in countries such as England, Italy, Switzerland and Japan, they are all of similar thickness as they all use the same technology. In some cases, the magnetic band does not exist as it is covered by the ink of the card's images, while in other cases the band is perforated to indicate the remaining credit.

b) Electronic cards (chips). These use a chip that stores all the information relating to the card's remaining credit. Most European countries use this method, which is also being adopted by countries from other continents, such as Japan. Around 10 types of chips are currently being manufactured.

c) Optical cards. These are Swiss-manufactured and boast a thin optical strip that, when slotted into the phone, is read by an infrared ray and is reflected by a detector. In many of these cards, a thermal ink is placed on the optical band, which darkens when heated up making the cards easier to read.