Capital markets trade longer-term financial instruments commonly known as Bonds (usually with a life of more than one year) and equity.
Primary capital markets are concerned with the initial raising of capital: that is selling new bonds and equity.
Secondary markets allow the original investors to sell on their investments to others, and this requires that the bonds or equity are listed on exchanges.
Yields on financial instruments with maturities of more than one year are commonly quoted on an effective annual rate basis.
(An exception to this being bonds with semi-annual interest payments, which are more commonly quoted on a semi-annual basis.)