A foundation in the United States is a type of charitable organization. However, the Internal Revenue Code distinguishes between private foundations (usually funded by an individual, family, or corporation) and public charities (community foundations and other nonprofit groups that raise money from the general public). Private foundations have more restrictions and fewer tax benefits than public charities like community foundations. http://en.wikipedia.org/wiki/Foundation_%28United_States_law%29

A charitable organization is a type of non-profit organization (NPO). The term is relatively general and can technically refer to a public charity (also called "charitable foundation," "public foundation" or simply "foundation") or a private foundation. It differs from other types of NPOs in that its focus is centered around goals of a general philanthropic nature (e.g. charitable, educational, religious, or other activities serving the public interest or common good). http://en.wikipedia.org/wiki/Public_charity

Community foundations (CFs) are instruments of civil society designed to pool donations into a coordinated investment and grant making facility dedicated primarily to the social improvement of a given place. http://en.wikipedia.org/wiki/Community_foundation