An NGO is a non-governmental organization which is non-profit and usually organized by citizens. These organizations can be involved in a wide range of areas including politics, health policy, economics, the environment or social welfare.
An IGO is an intergovernmental organization which is an entity created by treaty, involving two or more nations, to work in good faith, on issues of common interest.
These organizations create policy papers and publications which provide information on a variety of topics.