The next kind of plastic the banks want you to keep in your wallet is a smart card. They come in different varieties and most are not yet ready for a mass distribution, but, at this writing, pilot projects are forging ahead. Promoters of smart cards make the assumption that you don’t like to carry cash. You do not like fishing for bills and coins to buy a newspaper or a soda. You would to rather put down plastic instead.

This kind of card has money on it, embedded in a computer chip. A $50 card, for example, will give you $50 in spending power. If you buy a 5o cent newspaper, the seller will put your card in a special terminal and drain off 50 cents. Identification or signature is not required.

You now have a card with $19.25 left on it. After spending $1 on a soda, the value of your card goes down to $18.25. If you forget how much you have, you can check it with a little portable card reader. Some readers might also list the last five things you have bought.

If every merchant, street vendor, cab driver, and bus accepted smart cards, you would not have to have cash on your pocket. To some, that would be a huge convenience; to others, it is a shrug. If some merchants took smart cards and others did not, however, you would have to carry both.

What is in it for the bank? Eventually (although not at first), the bank will charge you for the card. There might be a fee when you accessed the ATM to load it up. The merchant would also pay a fee in return for getting what is presumably a more secure transaction.

What is in it for you? Convenience, maybe. Putting down a card is a tad quicker than pulling out cash. You always have the equivalent of exact change. You would not have to count you change (but you would have to use the card reader to be sure the merchant’s terminal deducted the right amount). You might also use the card to make small purchases over the Internet.

For a while, the smart cards probably would not have any more than $100 on them and the limit might be lower than that. So they are strictly for walking around money. You would still need your credit card, debit card, or checkbook for more serious shopping.

If the card malfunctions say, it registers $14 when you are sure you were carrying $36 the bank can check the balance on the computer chip.

Credit Card

Unauthorized Use: Here is what you have to pay if your credit card is stolen and charges are run up: Nothing if you reported the loss to the bank before a fraudulent charge occurred. Up to $50 for charges run up before the theft was reported to the card issuer and banks often waive even that small fee. Nothing if you still have your card, but your number was used fraudulently, for example, in a mail order transaction or a transaction over the internet. This covers both business and consumer transactions.

Billing Errors; you are fully protected against consumer billing errors. If you have already paid an erroneous bill, you will get money back.