The use of credit cards is increasing in China. There are three essential cards for residents in China to have. Not credit cards like Visa or MasterCard, and not ATM cash cards. Those cards are no doubt important in China, but the cards under discussion are more indispensable than those.

These are "electricity cards" used for paying your electricity for your household, "gas cards" for paying for the gas you need to cook, and "water cards" for the water you need to wash and bathe. It's one of the fundamental rules of living in China that households have to pay in advance, by filling up the cards, lest the supply of electricity, gas or water be abruptly cut off. It's quite burdensome to monitor at all times how much electricity, gas or water is left.

If you refuse to comply with this system, perhaps arguing its irrationality, you are bound to suffer the consequences. If the data stored on your computer evaporates because of a power stoppage in the middle of an important document, or if a faucet dries up just as you're preparing to head to work, you have nowhere to appeal to. That's not all. If you don't buy a cell phone charge card and deposit money in it, you're liable to see your phone account suspended. In principle you can pay later for local calls and Internet service, but you really only feel safe if you pay in advance. If you're a few days late in paying for your local calls, your phone makes a sound indicating it cannot be used.

Another Chinese rule that foreigners find difficult at first is the practice of paying security money. If exaggeration is permitted, it's safe to say that every transaction requires key money. As travelers find out in China, even people staying at five-star hotels have to pay a deposit -- about twice the hotel bill -- when they check in.

Of course you get your deposit back when you check out, except under extraordinary circumstances. When you rent a house you have to pay key money worth twice the rent. Overseas roaming for your cell phone requires a deposit of 3,000 yuan. Changing the payment scheme for your cell phone from pre-paid to post-paid takes a deposit of 3,000-4,000 yuan, and getting drinking water delivered takes 50-100 yuan per big bottle. The family of a patient transported to a hospital by an ambulance is said to have been asked to pay a deposit for the gurney, and a restaurant reportedly asked for a deposit for a stick used for skewered mutton.

More alarming is the fact that the Chinese take for granted these practices that foreigners find so inconvenient. When this reporter complained to a Chinese acquaintance that these rules are bothersome and inconvenient, he retorted, "It's much more convenient to buy electricity and water in advance, and the deposit is paid back later. What's so inconvenient about it?"

China, thanks to its strident economic growth, is treated as a member of the "G2" along with the U.S., it is claimed. But the country's advance payment culture, with its electricity cards and key money, displays China's too fragile software in comparison with its hardware. If you are to succeed in a joint venture with the Chinese, experienced Korean businessmen here say, you have to first establish a relationship of trust and confidence with your counterparts by drinking heavily and going to the baths together. This habitual Chinese distrust, some say, was aggravated by the 10-year dark age of the Cultural Revolution.

Credit transactions are rapidly expanding in China, too, with the number of stores where you can use credit cards increasing. Few young people working at reputable workplaces fail to carry at least one credit card. The distrust of credit, like the advance payment system, should gradually disappear with this trend. But it seems unwise to expect a profound shift in the consciousness of the Chinese people for the time being.

This column was contributed by Lee Myong-chin, the Chosun Ilbo's correspondent in China.