SSL makes purchasing online more secure than buying at a physical retail store. For the most part, when you open a secure connection to an e-commerce site, you are using SSL encryption. The secure server then keeps that information encrypted so no one can get access to your private information. In some cases, retailers and banks even transfer that information to a server that is not connected to the Net at all. But if your credit card is encrypted, it looks like a very long string of letters and numbers instead, so the sniffer cannot find it.
Many people seem to be hesitant to shop online because they believe it to be less safe.
However, the protection offered by SSL means that your credit card number will be seen by far fewer people than if you use it at a store. When you make a purchase at a physical store, there is a trail of paper left behind, containing your number in its entirety. If it falls into the wrong hands, that person can enjoy themselves at your expense.