When you make credit card purchases online or over the phone, you'll often need the card's security code to complete the transaction. The security code helps to protect you from credit card fraud ...

You may also have to share your card's security code, which you can find on the front or back of your card, depending on the credit card issuer. Your security code number adds extra protection ...

Forget passwords. If you want strong online security, you need to be using multi-factor authentication wherever you can. Here's how to get started. I've been writing about computers, the internet ...

This process, known as “two-factor authentication," adds an extra layer of security ... you can't get inside. Similarly, if you have the account password but not the verification code, you ...

so in theory only you should be able to get at a code sent to that number. It's a useful extra layer of security and means that if your usernames and passwords escape into the wild, they can't be ...