"A proposal offers to do something or recommends that something be done. A proposal's general purpose is to improve conditions, authorize work on a project, present a product or service (for payment), or otherwise support a plan for solving a problem or doing a job" (Lannon, Klepp & Gurak, 2015, p. 313). A request for proposals (RFP) is a document that solicits proposals.
Lannon, J.M., Klepp, D. & Gurak L.J. (2015). Technical communication (6th Canadian ed.).Toronto : Pearson Canada.