If you wish to travel to the European Union, there are two visa possibilities. Firstly, the Schengen visa, which will allow you to visit all countries within the Schengen area. The Schengen countries are: Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Portugal, Slovakia, Slovenia, Spain and Sweden.
Switzerland, Liechtenstein, Iceland and Norway are the four non-EU states who are part of the Schengen agreement. You will be able to visit them with your Schengen visa.
Bulgaria, Croatia, Cyprus, Ireland, Romania and the United Kingdom are part of the European Union, but not of the Schengen countries. For the United Kingdom and Ireland, you will need a separate visa. The other four states wish to join Schengen in the future and have special visa-free regimes for those who hold a Schengen visa or passport and as long as their visa allows at least two entries in Schengen space and the number of entries and/ or length of stay have not been not exhausted.
There are several types of Schengen visas. The Schengen type C allows you to stay for a maximum of 3 months/90 days in a six month period and allows for either single entry or multiple entries. The C-type visa is granted for several travelling purposes, such as tourism and business or for other needs. You determine the purpose of your visit in the documents which will be provided to the embassy to obtain visa. Embassy processes documents and prepare the answer on the basis of applied documents.
The D-type visa grants access to the Schengen area for a maximum of 180 days with a validity up to one year. For example, if you apply for a student visa and your studies last longer than 90 days, then you will have to apply for a permit of stay in the country of your studies, which will allow you to stay longer. The permit of stay will allow you to travel freely through the Schengen area. Similarly, you have to apply for a permit of stay if you travel to a Schengen country for working purposes and your stay in this country will exceed 90 days per in a six month period.
You should apply for the visa at the embassy of the country where you will enter the Schengen area or where you spend most of the time. The time period during which and application must be submitted to the diplomatic mission depends on the country. It is advisable to contact the relevant embassy or mission in order to learn when you have to apply. You also might have to book an appointment before lodging the application. Information about required documents and frequently asked questions can be found on the website of the EU: http://ec.europa.eu/dgs/home-affairs/what-we-do/policies/borders-and-visas/visa-policy/required_documents/index_en.htm
Secondly, the National visa is meant for those who wish to stay in, or visit one EU country, usually only for a short time. In order to apply for a national visa, you need to visit the embassy of the country you wish to reside in. The national visa will only grant access to this EU state and can be either single entry or multiple entries. For the most updated information on requirements and application procedures, please read the instructions on the website of the country you wish to visit.
A permit of stay is issued by national authorities only. Permit of stay can be either short-term or long-term. The short term permit is granted for a maximum of 5 years and is given for purposes such as work or study, or for family purposes. Permit of stay will grant you also access to the Schengen area. For details regarding the requirements to obtain a permit of stay, please review the websites of the country you wish to visit.