Charities & Non-profits – IRS

Charitable Organizations — IRC 501(c)(3)
Organizations that are organized and operated exclusively for religious, charitable, scientific, testing for public safety, literary, educational or other specified purposes.

Churches & Religious Organizations — IRC 501(c)(3)
Churches and religious organizations are among the charitable organization that may qualify for exemption from federal income tax under Section 501(c)(3).

Private Foundations — IRC 501(c)(3)
Private foundations typically have a single major source of funding (usually gifts from one family or corporation) and most primarily make grants rather than directly operate charitable programs.

Political Organizations
A party, committee, association, fund or other organization organized and operated primarily for the purpose of directly or indirectly accepting contributions or making expenditures, or both, for an exempt function.

Other Nonprofits
Organizations meeting specified requirements may qualify for exemption under subsections other than Section 501(c)(3). These include social welfare organizations, civic leagues, social clubs, labor organizations and business leagues.