Transit and short-term visas have fundamental differences
Short-term visa
So, firstly, a Schengen short-term visa is a document that can be valid for up to 3 months. The purposes of the trip are quite varied – business, tourism, private, that is, by invitation of a private individual, and so on. For example, what visa is needed for Italy? Usually a category C visa. It is issued for both business trips and tourism. In total, on the territory of the Schengen states, a foreigner can stay no more than 90 days within a 6-month period. This means continuous stay or the total sum of all stays over half a year.
Short-term visas have their own subcategories. C1 – a document valid for only 30 days, C2 and C3 – six months and one year respectively with 90-day permitted stay. Having obtained a C4 visa, you can enter Schengen countries without applying for a new permit for one to five years. However, you cannot circumvent the 90-day limit, even with such a serious document.
Furthermore, all short-term visas differ in the number of entries. Single-entry visas allow crossing the Schengen border once, multiple-entry visas several times. That is, a multiple-entry six-month Schengen visa via Poland means you can enter Schengen territory at any time within 6 months, but the total period of stay in Poland and other countries must not exceed 90 days.
Transit visa
Recently, transit passengers are entitled not to the usual category B visa, but to a short-term category C visa, but with the mandatory mark 'transit'. It is valid for only a few days – from 1 to 5, and is issued to foreigners who travel through a Schengen member state by land transport. For example, where to get a visa to Sweden? Of course, either at the consulate of that country or at a visa center. That is, in the same place where other types of visas are issued.
It is quite possible that you will need a category A document if you have a flight with a transit stop in Schengen territory. This visa gives the right to stay in the airport zone of any Schengen country. But keep in mind that leaving the airport into the city will be considered illegal.
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