The document provides an overview of the American Community Survey (ACS), describing what it is, how data is collected and released, and key differences between the ACS and the Decennial Census. The ACS is a large, continuous demographic survey that produces annual and multi-year population estimates for small areas. Data is collected each month and products are released the year after collection. The ACS uses a different methodology than the Census, with differences in residency rules, sample weighting, and how data is allocated. It produces estimates over time periods rather than a single point in time.