The 1950's era in the US being referred to as the "affluent society" represents a change in the American economy. After World War II, the American economy was booming thanks to the increased spending in developing military technology and creating the resources needed to help a post World War II Europe.
The result of this economic boom included lower unemployment rates and increased spending on material goods. A lot of this disposable income can be contributed in part to the GI Bill, which helped veterans of World War II pay for job training or pursuing a college degree. This then resulted in the development of the new middle class, which enjoyed modern luxuries like TV's and houses in the suburbs.