What’s the difference between a non-profit and an NGO?

Non-profit organization (rectangle) v. Nongovernmental organization (square, in the case they are non-profit NGOs) (A square is a rectangle but a rectangle is not a square):

nongovernmental organization (NGO) (Britannica Academic Edition)
“nongovernmental organization (NGO), voluntary group of individuals or organizations, usually not affiliated with any government, that is formed to provide services or to advocate a public policy. Although some NGOs are for-profit corporations, the vast majority are nonprofit organizations. Some NGOs, particularly those based in authoritarian countries, may be created or controlled by governments. By most definitions, political parties and criminal or violent guerrilla organizations are not considered NGOs. The issues addressed by NGOs run the gamut of human concerns (e.g., human rights, environmental protection, disaster relief, and development assistance), and the scope of their activities may be local, national, or international. Some NGOs fulfill quasi-governmental functions for ethnic groups that lack a state of their own. NGOs may be financed by private donations, international organizations, governments, or a combination of these.”

What is a Nonprofit? (About.com)
“The term, nonprofit, is used rather loosely to describe groups that come together to achieve a mission, rather than to make a profit.The term “nonprofit” does not imply any specific type of legal structure. If the group incorporates, it is a nonprofit corporation. If it does not incorporate, it is an unincorporated nonprofit association.”

Basic Overview of Nonprofit Organizations (Free Management Library)

• Suggested Previous Reading
  
• What is a Nonprofit?
  
• Key Roles
  
• Three Major Sections of Personnel in a Nonprofit
  
• Management Skills Generally Unique to Nonprofits
  
• Current Major Challenge: Devolution
  
• Revenue: Fees and Fundraising
  
• Unique Nature and Struggles of Traditional Small Nonprofits
  
• General Resources
  
• Additional Perspectives

Difference Between NGO and Non-Profit Organizations (DifferenceBetween.net):
“To summarize, the differences between a non-profit organization and NGOs are:

1. The NGO is a non-governmental organization. Its funds are raised by the government, but it maintains a non-governmental position, with no need for a government council. They are also known as civil society organizations.
2. A non-profit organization uses its extra funds for the purpose of the organization, rather than dividing it between the shareholders and the owners of the organization. Examples of NPOs are public arts organizations, trade unions and charitable organizations.”

Non-Profit Organizations & NGOs (http://faculty.washington.edu/krumme/readings/nonprofits.html)
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