HONG KONG, China - Confused by the rules and regulations of China's stock markets? You are not alone.

Probably one of the most common questions I am asked as Asia Business Editor is how to invest in China, especially its stock markets. The markets are up more than 80 percent this year. With the world economy in turmoil, many investors see China as a bright spot on an otherwise dark landscape. They want in.

Market watchers debate if China's stock markets are headed into bubble territory and warn that trading is still a new phenomenon in the country. Information is scarce, spotty, and often only in Chinese. Market swings are extremely volatile.

But with that warning in mind, here is a little guide to help the intrepid better understand China's stock investing ABC's.

A-shares: Stocks of Chinese companies listed in mainland China - in Shenzhen and Shanghai. These shares are sold in Chinese yuan, largely to local investors. Foreign individual investors cannot buy A-shares directly. International institutions can, but with limits. "China has a very restrictive policy in terms of allowing foreign investing into the local stock market," explains Peter Alexander of Shanghai-based Z-Ben Advisors. "They don't actually need foreign investors because there is enormous amount of demand locally." Alexander suggests going through a bank or a mutual fund.

B-shares: B-shares are also stocks of Chinese companies listed in Shenzhen and Shanghai. These stocks were originally meant for foreign investors and are sold in U.S. and Hong Kong dollars. The B-share market never really took off in the way the Chinese government intended. Chinese companies looking for foreign funds often choose instead to list on the Hong Kong stock market. The government has recently loosened the rules to allow more domestic investors to buy B-shares though the number of companies is pretty small.

H-shares: If anyone wants to trade in Chinese stocks directly, Alexander says Hong Kong is the place to do it. "Over the past decade, a number of Chinese companies have begun to list on the Hong Kong market," he told me. "Banks, petroleum companies, every type of industry, big companies, very liquid." These shares trade in Hong Kong dollars and are governed by international standards, so buying and selling H-shares is more transparent. Information on these listed companies, Alexander says, is easier to find.

ADRs: American Depositary Receipts. These are shares of non-U.S. – in this case Chinese - companies listed in New York. Investors can buy big Chinese names such as China Mobile or PetroChina but the selection is limited.

Investing in Chinese companies is a bit of a letters game - and, certainly, a risky one.