E.g., 12/06/2019
E.g., 12/06/2019

Immigration: The Basics

Immigration: The Basics

Welcome to Immigration: The Basics, a section of our website where we have gathered in one place explainers, data-rich fact sheets and articles, and data tools that we have created to offer basic, accurate facts about immigration and immigrants in the United States and internationally. We hope you will find the resources here useful as you seek to learn more about the phenomenon of international migration and some of the 258 million people globally who live outside their country of birth.

Recent Activity

Explainers
April 2019
By Julia Gelatt
Explainers
April 2019
By Jessica Bolter
Explainers
February 2019
By Jessica Bolter
Articles

Over the past several decades, in response to the uptick in spontaneous migration flows, there has been a surge in construction of border walls and fences. This trend begs several questions: Why now? Did border walls work in the past? Do they work today? This article examines the history of border barriers and assesses how effective they are at deterring unauthorized migration.

Explainers
April 2019

Through which visa categories can immigrants move temporarily or permanently to the United States? What are the main channels by which people come, and who can sponsor them for a green card? Are there limits on visa categories? And who is waiting in the green-card backlog? This explainer answers basic questions about temporary and permanent immigration via family, employment, humanitarian, and other channels.

Explainers
April 2019

How has the size of the unauthorized population in the United States changed over time? How is illegal immigration changing, and where do unauthorized immigrants come from? This explainer answers basic questions about illegal immigration, the changing patterns from Mexico, and more.

Explainers
February 2019

Who is an immigrant? Does that status change if, for example, a foreigner marries a native-born resident or serves in his or her adopted country's military? This explainer answers basic questions about international migrants—who they are, their top destinations, where they come from, how they are counted, and more.

Recent Activity

Explainers
April 2019

Through which visa categories can immigrants move temporarily or permanently to the United States? What are the main channels by which people come, and who can sponsor them for a green card? Are there limits on visa categories? And who is waiting in the green-card backlog? This explainer answers basic questions about temporary and permanent immigration via family, employment, humanitarian, and other channels.

Explainers
April 2019

How has the size of the unauthorized population in the United States changed over time? How is illegal immigration changing, and where do unauthorized immigrants come from? This explainer answers basic questions about illegal immigration, the changing patterns from Mexico, and more.

Explainers
February 2019

Who is an immigrant? Does that status change if, for example, a foreigner marries a native-born resident or serves in his or her adopted country's military? This explainer answers basic questions about international migrants—who they are, their top destinations, where they come from, how they are counted, and more.

Articles

Over the past several decades, in response to the uptick in spontaneous migration flows, there has been a surge in construction of border walls and fences. This trend begs several questions: Why now? Did border walls work in the past? Do they work today? This article examines the history of border barriers and assesses how effective they are at deterring unauthorized migration.