The maker of a note, in order to get money on it, often gives certain security which is known as "collateral" and is designed to insure the payee against the maker's inability to pay on maturity. Thus, A borrows $1,000 from B and gives B his promissory note for that amount. A also gives B (or puts in the hands of a third party) securities which shall be used to reimburse B if he, A, fails to pay the note when due. Suppose A fails to pay and the securities sell for $1,500. Then B will have to return to A $500 less interest on the note (if there is any). Thus, giving collateral makes security more specific.