Human migration

Human migration is the movement of people from one place to another, with intentions of settling, permanently or temporarily, at a new location. The movement often occurs over long distances and from one country to another, but internal migration is the dominant form of human migration globally.
Migration is often associated with better human capital at both individual and household level, and with better access to migration networks, facilitating a possible second move. It has a high potential to improve human development, and some studies confirm that migration is the most direct route out of poverty. Age is also important for both work and non-work migration. People may migrate as individuals, in family units or in large groups. There are four major forms of migration: invasion, conquest, colonization and emigration/immigration.
People moving from their home due to forced displacement may be described as displaced persons or, if remaining in the home country, internally-displaced persons. People who flee to a different country due to political, religious, or other types of persecution in their home country can formally request shelter in the host country. These people are commonly referred to as asylum seekers. If the application is approved, their legal classification changes to that of refugees.

Definition

Depending on the goal and reason for relocation, migrants can be divided into three categories: migrants, refugees, and asylum seekers. Each category is defined broadly as the combination of circumstances that motivate a person to change their location. As such, migrants are traditionally described as persons who change the country of residence for general reasons. These purposes may include better job opportunities or healthcare needs. This term is the most widely understood, as anyone changing their geographical location permanently is a migrant.
In contrast, refugees are defined by the UNHCR as "persons forced to flee their country because of violence or persecution". The reasons for the refugees' migration usually involve war actions within the country or other forms of oppression, coming either from the government or non-governmental sources. Refugees are usually associated with people who must unwillingly relocate as fast as possible; hence, such migrants are likely to relocate undocumented.
Asylum seekers are associated with persons who also leave their country unwillingly, yet, who also do not do so under oppressing circumstances such as war or death threats. The motivation to leave the country for asylum seekers might involve an unstable economic or political situation or high rates of crime. Thus, asylum seekers relocate predominantly to escape the degradation of the quality of their lives.
Nomadic movements usually are not regarded as migrations, as the movement is generally seasonal, there is no intention to settle in the new place, and only a few people have retained this form of lifestyle in modern times. Temporary movement for travel, tourism, pilgrimages, or the commute is also not regarded as migration, in the absence of an intention to live and settle in the visited places.

Migration patterns and related numbers

There exist many statistical estimates of worldwide migration patterns. The World Bank has published three editions of its Migration and Remittances Factbook, beginning in 2008, with a second edition appearing in 2011 and a third in 2016. The International Organisation for Migration has published ten editions of the World Migration Report since 1999. The United Nations Statistics Division also keeps a database on worldwide migration. Recent advances in research on migration via the Internet promise better understanding of migration patterns and migration motives.
Structurally, there is substantial South–South and North–North migration; in 2013, 38% of all migrants had migrated from developing countries to other developing countries, while 23% had migrated from high-income OECD countries to other high-income countries. The United Nations Population Fund says that "while the North has experienced a higher absolute increase in the migrant stock since 2000 compared to the South, the South recorded a higher growth rate. Between 2000 and 2013, the average annual rate of change of the migrant population in developing regions slightly exceeded that of the developed regions."
Substantial internal migration can also take place within a country, either seasonal human migration, or shifts of the population into cities or out of cities. However, studies of worldwide migration patterns tend to limit their scope to international migration.

Year	Number of migrants	Migrants as a % of the world's population
1970	84,460,125	2.3%
1975	90,368,010	2.2%
1980	101,983,149	2.3%
1985	113,206,691	2.3%
1990	152,563,212	2.9%
1995	160,801,752	2.8%
2000	172,703,309	2.8%
2005	191,269,100	2.9%
2010	221,714,243	3.2%
2015	243,700,236	3.3%
2020	280 598 105	3.6%

Almost half of these migrants are women, one of the most significant migrant-pattern changes in the last half-century. Women migrate alone or with their family members and community. Even though female migration is largely viewed as an association rather than independent migration, emerging studies argue complex and manifold reasons for this.
As of 2019, the top ten immigration destinations were:

In the same year, the top countries of origin were:

Besides these rankings, according to absolute numbers of migrants, the Migration and Remittances Factbook also gives statistics for top immigration destination countries and top emigration origin countries according to percentage of the population; the countries that appear at the top of those rankings are entirely different from the ones in the above rankings and tend to be much smaller countries.
File:Brooklyn Chinatown.png|thumb|Typical grocery store on 8th Avenue in one of the Brooklyn Chinatowns on Long Island, New York.
New York City's multiple Chinatowns in Queens, Manhattan, and Brooklyn are thriving as traditionally urban enclaves, as large-scale Chinese immigration continues into New York, with the largest metropolitan Chinese population outside Asia, The New York metropolitan area contains the largest ethnic Chinese population outside of Asia, comprising an estimated 893,697 uniracial individuals as of 2017.
As of 2013, the top 15 migration corridors were:

World economy

The impacts of human migration on the world economy have been largely positive. In 2015, migrants, who constituted 3.3% of the world population, contributed 9.4% of global GDP.
At a microeconomic level, the value of a human mobility is largely recognized by firms. A 2021 survey by the Boston Consulting Group found that 72% of 850+ executives across several countries and industries believed that migration benefited their countries, and 45% considered globally diverse employees a strategic advantage.
According to the Centre for Global Development, opening all borders could add $78 trillion to the world GDP.

Remittances

s form a substantial part of the economy of some countries. The top ten remittance recipients in 2018.

Rank

Country

Remittance

Percent of GDP

India

Voluntary and forced migration

Migration is usually divided into voluntary migration and forced migration. The distinction between involuntary and voluntary migration is difficult to make and partially subjective, as the motivators for migration are often correlated. The World Bank estimated that, as of 2010, 16.3 million or 7.6% of migrants qualified as refugees. This number grew to 19.5 million by 2014. At levels of roughly 3 percent the share of migrants among the world population has remained remarkably constant over the last 5 decades.

Voluntary migration

Voluntary migration is based on the initiative and the free will of the person and is influenced by a combination of factors: economic, political and social: either in the migrants' country of origin or in the country of destination. "Push-pull factors" are the reasons that push or attract people to a particular place. "Push" factors are the negative aspects of the country of origin, often decisive in people's choice to emigrate. The "pull" factors are the positive aspects of a different country that encourages people to emigrate to seek a better life. For example, the government of Armenia periodically gives incentives to people who will migrate to live in villages close to the border with Azerbaijan. This is an implementation of a push strategy, and the reason people do not want to live near the border is security concerns given tensions and hostility because of Azerbaijan.
Although the push-pull factors are opposed, both are sides of the same coin, being equally important. Although specific to forced migration, any other harmful factor can be considered a "push factor" or determinant/trigger factor, such examples being: poor quality of life, lack of jobs, excessive pollution, hunger, drought or natural disasters. Such conditions represent decisive reasons for voluntary migration, the population preferring to migrate in order to prevent financially unfavorable situations or even emotional and physical suffering.