I have traveled to Mexico a couple of times.
Mexico is cool.  It is officially known as the United Mexican States.
How does it relate to the United States?
Well, the US resides along it's northern border, of course.  Size-wise, it the 6th largest country in the Americas.
How does it compare in terms of income to the US?
of over 129 million people, Mexico is the tenth most populous country and the most populous Spanish-speaking country in the world, while being the second most populous nation in Latin America after Brazil. Mexico is a federation comprising 31 states plus Mexico City (CDMX), which is the capital city and its most populous city. Other metropolises in the country include Guadalajara, Monterrey, Puebla, Toluca, Tijuana, and León.
Pre-Columbian Mexico dates to about 8000 BC and is identified as one of six cradles
, the INM deported 188,000 people at a cost of US$10 million.
In September 2007, Mexican President Calderón harshly criticized the United States government for the crackdown on illegal immigrants, saying it has led to the persecution of immigrant workers without visas. "I have said that Mexico does not stop at its border, that wherever there is a Mexican, there is Mexico", he said. However, Mexico has also deported US citizens, deporting 2,000 cases in 2015 and 1,243 in 2014.
Illegal immigration of Cubans