Authorization. This term refer to an action taken by Congress through variety of legislative measures. In terms of the Congressional Budget process, it usually denotes an “authorization of appropriations”. This typically takes the form of an authorizing committee establishing and structuring a program administered by a Federal agency, which is then later funded by the Committees on Appropriations in a later bill (or joint resolution). Of great significance is that the authorization itself is not a “scoreable event”, which denotes an action taken by Congress which has an effect on budget authority, outlays, or revenue.
Another form of “authorization” occurs, though, by Congress giving a permanent indefinite appropriation, which acts as a form of authorization and appropriation combined:
a “permanent indefinite” appropriation is open ended as to both period of availability and amount. Examples are 31 U.S.C. § 1304 (payment of certain judgments against the United States) and 31 U.S.C. § 1322(b)(2) (refunding amounts erroneously collected and deposited in the Treasury).
Source: GAO, Principles of Federal Appropriations Law, 4th ed., 2016 rev., ch. 2, GAO-16-464SP (Washington, D.C.: Mar. 2016), page 2-11.