Email: as private as a postcard

"Don't put anything in an email that you wouldn't want to see on the evening news."

The real world equivalent of an email is a postcard. When you send a postcard you know that a lot of postal workers can read it if they want to, but they'll probably be too busy to bother.

Email is the same. Your message has to pass through many networks to get to its final destination, and all the network managers can read your mail if they feel like it. Fortunately, they're well-paid, honest people, and they've got more important things to do.

The one time you can guarantee that your mail will be read is if the transfer goes wrong. Network managers receive their big salaries for making sure everything works as it should, and they install systems that automatically tell them if something goes amiss. Your wonky mail will pop up on their screen along with an error message, giving them the chance to correct the problem and make sure it gets to its destination.

Since they're such an honest bunch, they'll probably just shake their heads and sigh when they see all that confidential information you've included in your message. Unless it's something highly illegal.

If you're sending and receiving mail at work, your mail may be intercepted by your company for security reasons. They have every right to do this and you won't know it's happening. You can read more details about this in the Data section. But if you use Web mail for personal correspondence at work (like Yahoo Mail or Hotmail) it's far less likely to be intercepted.

Police and security services can easily read you mail but rarely bother unless you're a very dodgy character.

Hackers do break into email servers and networks from time to time, but even when they do, they've usually got bigger fish to fry and don't thoroughly inspect the mail that's there.

It is possible for snoopers to install a "sniffer" on the Internet that intercepts all your incoming or outgoing mail. It's very hard to protect against this.

If you must send confidential information over the Internet, you need to encrypt it. Any kind of public key encryption, such as PGP, will make the content safe from everybody except national security services. And they'll only bother if you're a major criminal, terrorist, or a big foreign company they want to spy on.

Don't let all this put you off sending those email postcards. They're safe enough. Email is a less secure than your telephone or normal post, but still safe enough for most purposes.