Redlining refers to the discriminatory practice of denying or limiting financial services, such as mortgages, to certain neighborhoods based on the racial or ethnic composition of the area. This practice was widespread in the United States in the 20th century and it was based on the idea that certain neighborhoods were considered too risky to lend money to, due to the racial makeup of the area. It had a significant impact on African-American and other minority communities, as it made it harder for them to get mortgages and own property, this also reduced the value of their properties and limited their ability to build wealth through real estate.