The largest ETFs in the category include iShares iBoxx High Yield Corp Bond Fund ETF (NYSEArca: HYG) and SPDR Barclays Capital High Yield Bond ETF (NYSEArca: JNK).

As yields on traditionally safe Treasury bonds hover around historic lows, investors have turned to high-yield exchange traded funds to meet their income needs. [ETF Spotlight: High-Yield Bonds]

iShares iBoxx High Yield Corp Bond Fund ETF