Immigration
In short
The movement of people into a country or region where they are not native to settle as permanent residents. This process differs from short-term visits like tourism or commuting.
In plain words
It is when people move from their home country to live in a new one for a long time. They often move to find better jobs, safer homes, or to join family members.
A simple example
A person moving from Italy to the United Kingdom to start a new job and live there permanently is an immigrant. A person visiting London for a one-week holiday is not an immigrant.
Why it matters
It affects the economy, culture, and population size of both the home and host countries. It can help fill job shortages in one nation while changing the social makeup of another.
Easy to mix up
Do not confuse immigration with emigration, which is the act of leaving one's own country.