The HOLC (Home Owners' Loan Corporation) was created in 1933 as part of the New Deal to help homeowners who were struggling to make their mortgage payments during the Great Depression. The HOLC refinanced mortgages at lower interest rates and longer terms, and also provided loans to homeowners who were behind on their payments.
The FHA (Federal Housing Administration) was created in 1934 to insure mortgages for low- and moderate-income families. The FHA set standards for housing construction and lending practices, and also provided loans to home buyers who were unable to obtain financing from private lenders.
The USHA (United States Housing Authority) was created in 1937 as part of the New Deal to provide public housing for low-income Americans. The USHA built and operated public housing projects, and also provided loans to local housing authorities to build their own public housing projects.
These three agencies played an important role in providing affordable housing for Americans during different periods of time.