Exchange Traded Funds (ETFs) have recently become somewhat popular. At their heart, they are basically just index mutual funds which are bought and sold as stocks. In that way, they are similar to closed-end mutual funds which happen to be index funds. However, they have several interesting features which make them more similar to conventional (open-end) index mutual funds.

An obvious question is, "Which should I use, ETFs or conventional index mutual funds?"

This web page lists pros and cons of ETFs as compared to conventional index mutual funds.