Investing in the stock market hasn't paid off well lately. But what about bonds? It all depends. And, as with stocks, venturing into the world of bonds requires study and caution. Get those at these sites.

Bond basics. This site by the Securities Industry and Financial Markets Association, a trade group, has information for people just considering bond investments and for seasoned investors. It bills itself as a "source of bond price information and includes a wide variety of market data, news, commentary and information about bonds." Click on "bond basics" for descriptions of U.S. government, corporate, and municipal bonds. The glossary will clue you in to the meanings of terms such as "yield curve," "tranche," and "sinker."

http://go.philly.com/bonds1

Investment FAQ. The tutorial here starts out: "A bond is just an organization's IOU; i.e., a promise to repay a sum of money at a certain interest rate and over a certain period of time." After that, things get as complicated as you're willing to tolerate. The site is a collection of frequently asked questions about investing and personal finances. Articles we clicked on explained bond ratings, municipal bond terminology (sure, we wondered what an ad valorem tax was), and amortization.

http://go.philly.com/bonds2

How to. The How To Do Things site covers all sorts of things, including sports, hobbies, and travel. Its area on stocks and bonds has recent entries on how to buy bonds, how to diversify into bonds, how to invest in corporate bonds, and how to buy U.S. savings bonds. Its latest entry, though, was "How to make a stock investment."

http://go.philly.com/bonds3

Bond rating. The agencies that rate bonds and other financial "instruments" came under fire in recent months for not catching the implosion of securities tied to now-infamous subprime mortgages. You can read up on these agencies and what they do from this page at About.com.

http://go.philly.com/bonds4

Contact staff writer Reid Kanaley at 215-854-5114 or rkanaley@phillynews.com.