What is an ATM Machine?

An Automated Teller Machine (ATM) is a machine that lets people access their bank accounts, get money and check their balances without having to visit a bank teller. Many ATM machines will also let people deposit a check, transfer money from one account into another and some will even allow people to buy stamps.

How do they work? When a customer puts their bank card in the ATM, a message is sent to a Host Computer. This computer then sends another message to your bank. It is basically asking the bank if you have enough money in your account and it then sends a yes or no message back to the Host Computer. If the message is yes, then you will be able to get money from the ATM machine. If the message is no, you will not be able to get money from the machine.

But that is not the end of the story. You still need to pay for the money that you got from the ATM! Your bank will remove the money from your account and send it to the bank that owns the ATM. In a way, you "borrowed" money from the ATM machine and will later pay it back from your account. This is all done electronically. Some transactions are "live", meaning they come out of your account instantly, and others may take a day or two to complete the entire process. (For example, if the transaction happens on Saturday, you may not actually pay it back until Monday, when the bank opens again.

Have you ever wondered how an ATM machine knows how to count the money? The ATM has an electric eye that counts each bill as it exits the dispenser. This and other information regarding your transaction is recorded in a electronic journal. (Although it's more fun to think of someone sitting inside the machine writing it all down in a notebook!)

The ATM machine also has a sensor that checks the thickness of each bill. If two bills are ever stuck together, they will shoot out into a reject bin. Old money or worn and torn bills will do the same thing.

ATM machines are extremely accurate, but you should always count your cash just to double check. Just don't do it if there is someone standing behind you for safety reasons!

Do you know why ATM machines have Braille on them? Braille allows visually impaired people to walk up to an ATM in a drive thru and use it. The bank wants to be fair to everyone, so they make sure the machines can be used by everyone.

Here are some interesting facts to stump your friends with:

What is the most popular day that people use ATM machines? Friday!

An ATM machine can hold about 2,500 bills. If those are all $20 bills, then the ATM machine could have as much as $50,000 in it!

How much does an ATM machine weigh? About 1,500 pounds! Not quite a ton, but I don't think anyone will be walking away with an ATM machine on their back!

When a card is inserted into an ATM, it reads all the account information from a small magnetic strip on the back of the card.

When did the very first ATM make it's appearance? In 1969, in Long Island, New York.

ATM machines belong to a network that is shared by other banks around the world. If you live in the United States, but are at an ATM machine in France, it will still be able to access your account.

It's not quite the same as using a live teller though. ATM cards have limits on them. That means you can only take out a certain amount of money each day. This is to protect you should your card get lost or stolen.

Which brings me to my last point. If or when you get your own ATM card, NEVER write your PIN number on it. A PIN number (Personal Identification Number) is a secret code that gives your card permission to work. Kind of like a password on your computer.