In the United States, federal grants are economic aid issued by the United States government out of the general federal revenue. A federal grant is an award of financial assistance from a federal agency to a recipient to carry out a public purpose of support or stimulation authorized by a law of the United States. Grants are federal assistance to individuals, benefits or entitlements. A grant is not used to acquire property or services for the federal government's direct benefit. Grants may also be issued by private non-profit organizations such as foundations, not-for-profit corporations or charitable trusts which are all collectively referred to as charities. Outside the United States grants, subventions or subsidies are used to in similar fashion by government or private charities to subsidize programs and projects that fit within the funding criteria of the grant-giving entity or donor. Grants can be unrestricted, to be used by the recipient in any fashion within the perimeter of the recipient organization's activities or they may be restricted to a specific purpose by the benefactor.