Immigrants are people from other countries, of different nationality, may be also culture and hence religion that come to live in another country. Nb the term is used for people who are already installed and settled in the foreign country, as foreigners, and are allowed to stay for a while though posessin of Visa. Visa is he paper, that applies as permit of staying for a while, only, (within frame of Private International Law), on the average, 'white visa for ex. in Greece for immigrants, for staying only until a predefined date, then 'Visa' of colour 'rose' that involves temporary staying, and then it can be renewed, if some factors and conditions concur in 'this' case as it's defined by Law; or as it's defined in bilateral agreement of two countries, country of origin and country of immigration. And finally application of Green Visa, when this person, having renewed his/her visa, or for other factors, has found a permanent job, and thus live, in dignity like all other citizens of city or town where he/she came, and thus obtains this 'official' document for permanent staying. These are often called 'financial immigrants' who come to a place, for ex. having been political refugees, dur war, etc, come and settle with their family, in order to work, and then this can turn to permanent staying, and documents, on basis of factors described as above.

Between some countries, there is no need of Visa at all, according to applicable Law. Immigrant applies as general terms and in above cases, it included evading refugees, in some countries and places for specific reasons, mainly political ones, due war etc. who are not actually legal immigrants, thus they come without papers at all, and they'll either stay, according to general applicable regulation, of state of immigration, or they'll be forwarded back to their countries, after a while, upon decision of state, and sometimes, local authorities.

According to their 'legal status of immigration' if an immigrant commits a crime, he/she will either be judged and if so..condemned by local Court, or if kind of crime is such, then for reasons of social protection, and on basis of what applies between the two countries (country of origin and immigration), this person may be forwarded, thus sent to his/her own country to be judged there.

Sometimes we have massive expels of immigrants to their countries, if they have no other 'legal source' and on basis of initial status of immigration, by taking into account, job, penal status etc, then groups of immigrants may be sent back to their country of origin massively..

For ex. between countries of Shengen Convention, treatment of status of immigration applies in terms of equality and mutuality, and then each reason for immigrants to be sent back to their country, or judged in place of crime committed or penal act, is further discussed, depending on all these factors that concern person, and any further rules of Law, applicable at specific level, between these two countries-members, immigration and emigration, thus specific rules that apply per case, included exemptions for each one, and always per case. (and of course as always and in the frame of what Law describes..)