Illegal immigration refers to the act of entering or residing in a country without the legal permission required by that country's laws. This can occur when individuals cross borders without proper documentation or overstay their visas. People may seek to immigrate illegally for various reasons, including economic opportunities, safety from conflict, or family reunification. Countries often have laws and policies in place to manage immigration, and illegal immigration can lead to legal consequences for those involved. Governments may implement measures to control illegal immigration, such as border security and enforcement actions, while also addressing humanitarian concerns related to migrants' rights and welfare.