The section 501(c)(3) constitutes the section that is part of the US Internal Revenue Code that permits exemption from federal taxation for nonprofit organisations, particularly those classified as private foundations, public charities and private foundations operating for profit. It is administered and regulated through the US Department of Treasury through the Internal Revenue Service.

To be able to be considered tax-exempt, 501(c)(3) is the nonprofit must be established for at least one of the following exclusively charitable goals:

Religious
Charitable
Scientific
Evaluation for Public Safety
Literary
Educational
Promotion of international or national amateur sports, as well as
Prevention of cruelty towards animals and children
https://www.lotuspetalusa.org/501c3-guide/