Email is a great way to keep in touch with people, but it's also a great way for people you don't know or care about to get in touch with you.

Our inboxes are filled with unwanted adverts, annoying messages that try to get you to visit websites loaded with viruses, fake emails from banks that want you to hand over your secret password and invitations to visit pornographic websites.

It's called 'spam', it's been with us for years despite many efforts to solve the problem, and it doesn't seem to be going away any time soon.

If you get a new email address it might take a few weeks for the spammers to find you, but once they do you'll never get away. The emails are sent in their billions to addresses gathered by looking on websites.

Lots goes to non-existent email addresses created by generating every possible name for a popular internet provider, even nonsense like 'ahrqyfg@aol.com', just in case it's a real address.

If you ever reply to a spam message, perhaps telling them to stop hassling you, you'll get even more messages in future as the annoying spammers know that your email address is a genuine one.

And if you click on a link in an unwanted email you might find your computer infected with a virus or other nasty software.

But it seems that spam is profitable for the people sending it. American researchers tracked emails advertising fake drugs, including fake versions of Viagra, and they reckon that about one in every twelve million messages sent out results in a sale.

That may not sound much, but with billions of emails going out each day they think that it amounts to around $9,000 a day, more than enough to cover costs and make a profit.

And the websites used to sell the fake drugs probably steal credit card details too, making their owners even more money.

If you are getting spam then you can teach your mail program to spot it and throw it away. This works whether you're reading email on a website, like Googlemail, or using a programme like Microsoft Outlook or Apple Mail.

But in the end, it comes down to us. If nobody ever opened spam messages, replied to them or clicked on the links in them then the people sending them might decide to go and do something more useful.

Link:

Have a look at SmartScreen from Microsoft

My children rarely listen to CDs these days, preferring to get their music on their computers or portable players. If they do buy a new CD then it goes into the computer to be copied - or 'ripped' - and then just sits on the shelf.laptop, my phone and my mp3 player.

They also buy songs over the internet, cutting out the CD bit altogether. It is certainly simple to buy music on the web, with dozens of online stores offering millions of tracks to anyone with a credit card and an internet connection.laptop, my phone and my mp3 player.

The best known and most popular is Apple's iTunes Music Store, but HMV, Tesco and Play.com are also successful.laptop, my phone and my mp3 player.

And the mobile phone companies are also getting into the act, letting customers download music directly onto their phones.

Most of the songs on our computers are held as MP3 files. MP3 is the way that the music is converted into the pattern of '1's and '0's that the computer understands.

Although it's easy to buy songs it can sometimes be complicated to listen to them.

When my son buys a song from iTunes I can't listen to it on my laptop because most music from Apple is locked to a particular user and can only be played on their computer or MP3 player.

This is done using DRM, or 'digital rights management'. It is designed to stop people giving away copies of songs, but it can make life difficult for people who don't want to break the law.

Some of the biggest download sites sell music that can be played on any device, and they now have a special logo to show that the songs you buy from them are portable.

The 'MP3 compatible' logo is a good idea, especially as more of us have more than one computer in the house and devices that can play MP3s become more common.

After all, I should be able to buy a song once and know I can listen to it on my laptop, my phone and my mp3 player.

Link:

New MP3 logo gets online support