From the U.S. Web Design System website:
Empowered agency digital teams share solutions and use effective human-centered design practices.
USWDS is a design system for the federal government. We make it easier to build accessible, mobile-friendly government websites.
USWDS was created by a collaborative team at 18F and the U.S. Digital Service in 2015, under the guidance of an advisory board of talented, experienced government workers in the Consumer Financial Protection Bureau, Food and Drug Administration, Department of Veterans Affairs, Social Security Administration, Department of Education, Internal Revenue Service, and GSA.