This seemingly simple term, without a qualifier, can be rather confusing.

For example, there are two stock dividend yields. If you buy a stock for $30 (cost basis) and its current price and annual dividend is $33 and $1, respectively, the "cost yield" will be 3.3% ($1/$30) and the "current yield" will be 3% ($1/$33).

Bonds have four yields: coupon (the bond interest rate fixed at issuance), current (the bond interest rate as a percentage of the current price of the bond), and yield to maturity (an estimate of what an investor will receive if the bond is held to its maturity date). Non-taxable municipal bonds will have a tax-equivalent (TE) yield determined by the investor's tax bracket.

Mutual fund yields are an annual percentage measure of income (dividends and interest) earned by the fund's portfolio, net of the fund's expenses. In addition, the "SEC yield" is an indicator of the percentage yield on a fund based on a 30-day period.

Read more: http://www.investopedia.com/terms/y/yield.asp#ixzz1loc4aOwM