Immigration is and has been a big topic throughout the history of mankind. Especially the history of the United States of America is a history of immigration. Usually, single persons or families are the one's that leave their country to start a new life in another place. In some rare cases, there have been mass-immigration due to natural catastrophes and wars.
Some people leave their country voluntarily; some people are forced to leave the country. 2 factors play an important role for the decision to emigrate:
1. The situation in the current country.
2. The expected situation in the host country.
Many people emigrate to improve their work- or living conditions. Other would like to escape the tax authorities, or would just like to reduce their tax burden. Especially pensioners that have a secure and stable stream of income in the form of a pension emigrate to low-wage countries in order to save on every-day living costs. Other popular emigration reasons are friends and family abroad and welfare state tourism. This last reason is especially problematic as the welfare state tourists are usually stigmatized by the local population in the host country.
Many people also underestimate the kinds of problems they might encounter in the host country. Especially problems in handling the local language can lead to huge integration problems, which in turn lead to stigma and unemployment. This is why one should invest into getting information about the home country and its culture, and especially into language courses. If language courses are too expensive, computer programs that can teach the basics of a language will do.