ETFs: Advantages & Uses.

Here is a basic list of the advantages of ETFs from Wikipedia. Highlights are mine.

ETFs generally provide the easy diversification, low expense ratios, and tax efficiency of index funds, while still maintaining all the features of ordinary stock, such as limit orders, short selling, and options. Because ETFs can be economically acquired, held, and disposed of, some investors invest in ETF shares as a long-term investment for asset allocation purposes, while other investors trade ETF shares frequently to implement market timing investment strategies. Among the advantages of ETFs are the following

Lower costs - ETFs generally have lower costs than other investment products because most ETFs are not actively managed and because ETFs are insulated from the costs of having to buy and sell securities to accommodate shareholder purchases and redemptions. ETFs typically have lower marketing, distribution and accounting expenses, and most ETFs do not have 12b-1 fees.
Buying and selling flexibility - ETFs can be bought and sold at current market prices at any time during the trading day, unlike mutual funds and unit investment trusts, which can only be traded at the end of the trading day. As publicly traded securities, their shares can be purchased on margin and sold short, enabling the use of hedging strategies, and traded using stop orders and limit orders, which allow investors to specify the price points at which they are willing to trade.
Tax efficiency - ETFs generally generate relatively low capital gains, because they typically have low turnover of their portfolio securities. While this is an advantage they share with other index funds, their tax efficiency is further enhanced because they do not have to sell securities to meet investor redemptions.
Market exposure and diversification - ETFs provide an economical way to rebalance portfolio allocations and to "equitize" cash by investing it quickly. An index ETF inherently provides diversification across an entire index. ETFs offer exposure to a diverse variety of markets, including broad-based indexes, broad-based international and country-specific indexes, industry sector-specific indexes, bond indexes, and commodities.
Transparency - ETFs, whether index funds or actively managed, have transparent portfolios and are priced at frequent intervals throughout the trading day.
Some of these advantages derive from the status of most ETFs as index funds.

Source of this article: Wikipedia: http://en.wikipedia.org/wiki/Exchange-traded_fund.

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