What is Procurement Documents (RFP, RFQ, IFB)?
The three bid documents map to what the buyer knows: RFQ (request for quotation) — commodity purchase, price is essentially the whole decision. IFB (invitation for bid) — large, fully specified work; sealed bids, lowest responsive price wins. RFP (request for proposal) — the buyer has a problem, wants the seller's approach as well as a price, and evaluates against weighted criteria.
Exam cue: if the scenario cares only about price, RFQ/IFB; if it asks "how would you solve this?", RFP.
Worked example
The same data-center program issues all three: an RFQ for 400 identical racks (cheapest compliant quote wins), an IFB for the fully drawn civil works (sealed bids against complete specs), and an RFP for the security-operations partner — where methodology, staffing, and references outweigh price in the scoring sheet.