The U.S. census counts every resident in the United States. It is mandated by Article I, Section 2 of the Constitution and takes place every 10 years. The data collected by the decennial census determine the number of seats each state has in the U.S. House of Representatives and is also used to distribute billions in federal funds to local communities.
Census information affects the numbers of seats your state occupies in the U.S. House of Representatives. And people from many walks of life use census data to advocate for causes, rescue disaster victims, prevent diseases, research markets, locate pools of skilled workers and more.
The 2010 Census resulted in the first major change in the US Census of Population and Housing in over 150 years. As a result, it will be difficult to draw exact correlations between the 2010 Census and the previous decennial census reports.
In the recent past, two different forms were used. The "short form" went to most people and a randomly selected group got the "long form." The long form included all the questions on the short form and additional detailed questions.
In 2010 everyone got the same form.