Depending on the age of your child, you might not have worried about giving them too much guidance on selecting passwords for their online accounts and activities. Let’s face it, who’s really going to bother secretly cracking a six-year-old’s access-word for Club Penguin? (Other than his seven-year-old brother, and that would probably be loudly heralded with a chorus of “nah-nah na-na nah”s).

But with our growing reliance on passwords for everything from hiring a DVD to withdrawing your lifesavings, it’s good practice for even younger children to get into the habit of choosing, remembering and being protective of their passwords.

In an effort to create a password that you may actually remember when the pressure is on and 27 people are lined up behind you at the ATM, we often fall into the trap of choosing passwords that are pretty obvious. Your dog’s name, your child’s name, your maiden name, your wedding anniversary, your postcode, your address, your birthdate – all fall into the obvious category.

With password-cracking technology readily available – often for free on the Internet – even everyday, seemingly obscure words aren’t necessarily safe. These tools or programs process enormous quantities of letter and number combinations until a match is found. The simplest password crackers use a word list or dictionary program to generate millions of possible matches.

The best passwords mean something memorable to you, but wouldn’t be randomly guessed by others. SecurityFocus, an independent Internet security advisory site, suggests combining ‘length, width and depth’ when you create a password.

Length: Simply put, the more characters your password has, the lower the probability that it can be randomly cracked. Some sites require a maximum of six characters, some let you use more.

Width: This refers to the diversity of characters you use – not just sticking to lowercase letters. SecurityFocus suggests, as a general rule, using the following character sets in every password:

• uppercase letters such as A, B, C (where the site is case sensitive, i.e. can tell the difference between B and b);
• lowercase letters such as a, b, c;
• numerals such as 1, 2, 3;
• special characters such as $, ?, &; and
• Alt characters such as µ, £, Æ.

Depth: Passwords with depth have complex meanings.  Experts suggest phrases, as they allow you to introduce complexity but are still easy to remember. Even better is a mnemonic phrase with words spelled phonetically.  An example of this could be ‘YWoodiT3ll?’ (This can be remembered as ‘Why would I tell?’ and substitutes the number 3 for the letter e).

Of course, there is one obvious side-effect to giving your kids top-secret knowledge like how to create an uncrackable password. It puts the pressure on you to lift your security too. Because from here on in, your dog’s birthday just isn’t going to keep curious young minds out of your private email account!