Commercial Paper
Also called: CP, short-term corporate debt
Commercial paper is unsecured short-term corporate borrowing, usually under 270 days, used to fund payroll, inventory and receivables. It's cheap while it works and vanishes when it doesn't: the market is a confidence market, and in 2008 it froze within days, stranding blue-chip issuers who had assumed they could always roll it. That episode is the textbook example of liquidity risk being a funding structure problem, not an asset quality problem.