11 February 2014 is Safer Internet Day.
That's a European initiative aimed at helping youngsters to enjoy the internet without putting themselves at risk.
Last year at this time, we published ten short and simple Top Tips for young children and teenagers online.
This year, we thought we'd remind you of those tips, keeping them even shorter and simpler, so that they're easy to remember.
As you read them, you may find yourself thinking, "Those tips are too restrictive. Only an old timer or a wet blanket would be so strict."
For example, we're about to tell you not to friend people on Facebook unless you actually know them, which sounds as though we might as well be saying, "Don't use this new-fangled online Facebook stuff at all. Your grandparents didn't need it, and you don't either."
We're not really wet blankets.
We know that, sometimes, you will want to friend people on Facebook precisely because there's no way to communicate with them otherwise - perhaps you live in Kenya and your potential new friend lives in New Zealand.
Our online Tips aren't absolute or inflexible rules, and from time to time you may choose to "break" them.
What we want you to do is to start from a position of caution.
Then, "break" our online rules only when you have thought carefully about doing so (and, ideally, after you have asked your parents' advice).
Remember that a lot of online services rely on an approach called opt out.
That means they assume that the features of their service are so fantastic that everyone is going to want to use them, so they choose them for you anyway.
Then they give you a way to turn those features off at a later stage, if you ever get round to it (that's what is meant by opting out).
We suggest taking an opt in approach.
Don't do what everyone else is doing because Facebook, or Google - or Sophos, for that matter - made it the default.
→ Where computers are concerned, the word default means the choice that is made for you automatically if you don't take the time to choose for yourself.
Don't be a sheep.
After all, if those features are that good, you can always turn them on for yourself, after you've made your own mind up.
So here come our Top Ten Tips.
We've made them restrictive so you learn to stop and think first before you make online decisions, or let other people make decisions for you.
Once you have given something out online, it's hard to change your mind later and get it back.
But if you don't give it out at first, you can always choose to do so later, after you've had a think about it.
Limit your Facebook profile to your friends only.
- Accept online friend requests only from people you already know, and like, and trust.
- Only upload things you are happy for the whole world to see, including your parents, friends and even your enemies.
- Never give out your address or agree to meet in person someone you've "met" online.
- Set a password lock on your phone or any other device you use, and make sure it locks automatically when you aren't using it.
- Don't click on suspicious-looking links.
- Tell your friends in person if you receive unusual messages from them. (Someone could have stolen their passwords.)
- Always log out - don't leave any account open when you go away from your computer, phone or other device.
- Don't pick easy passwords - mix up letters, numbers and funny characters so other people can't guess what you chose.
- If you see something upsetting, or dangerous, or dishonest, speak up! Tell a parent or a teacher.
If you'd like to learn more about computer security in general, you might like to take a look at our Threatsaurus.
It's a clear and informative compendium of computer threats, written in plain English, and it doesn't talk down to you like some "expert guides" do.
Best of all, you can tell your parents and your grandparents about it too. (They may not have needed Facebook back in the day, but I bet they'd have used it if they'd had it!)
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