For the most part, ETFs are pretty similar regardless of which issuer is behind the fund. But as many investors know, there’s one notable exception to this rule. The HOLDRS products from Merrill Lynch are similar to traditional ETFs in many ways, but also feature some nuances that make them very different in others. HOLDRS stands for Holding Company Depository Receipts, and are securities that represent an investor’s ownership in the common stock or ADRs of specified companies in a particular industry. HOLDRS are designed to offer investors a way to achieve exposure to a basket of stocks in a cost-efficient manner while preserving ownership benefits related to the underlying stocks.

Below, we profile five facts about HOLDRS every investor should know before making an investment:

One of the most important influences on an investment's performance is underlying economic growth. That’s why PIMCO’s Bill Gross suggests investors direct their risk-taking towards fast growing countries that are less levered and less easily prone to bubbling.

The risk of investing in China is that stocks often appear to trade less on rational factors and more on the rumors, gossip and government intervention. Just last month China's government clamped down on bank lending in an attempt to harness China's rapid economic growth, which impacted stocks. Also, the homegrown market is effectively a closed shop which is not open to foreigners. However, there are dozens of Chinese companies traded in the U.S. exchanges.

I access the web each day from at least seven browsers:

• Chrome (GOOG) on my Macbook Pro (AAPL),
• Firefox on my Macbook Pro,
• Chrome on my Windows (MSFT) desktop in the office,
• Firefox on our "kitchen laptop",
• Safari on our "kitchen laptop",
• The Android browser on my Google phone,
• The Blackberry browser on my Blackberry 9700 (RIMM)

I know that I am not your typical web user. I keep both Firefox and Chrome open at the same time on my main machine (my Macbook Pro). I use three machines most every day, my Macbook, my office desktop, and our "kitchen computer". And I use two mobile devices every day.