Electronic mail has to be IT's "killer app" (to use another irritating abbreviation for an "outstanding application of technology"). It's one of the most cost-effective and efficient ways to communicate and send/receive data. You can send several messages for the cost of a phone call and in far less time than it takes to write a traditional letter.
It's a casual means of communicating - typing errors are par for the course - and e-mail protocol (good manners) demands that e-mails are answered pretty much as soon as they're read, which ensures a speedy response. Again you may find yourself up to your fingertips in abbreviations like "18r" (later), CU2NYT (see you tonight) or ;) which is a wink.
Being able to send attachments is arguably the best part of e-mails. Whether it be photos of the family or documents and spreadsheets, there is no simpler, more effective way of transferring them. There have also been recent software developments, like Acrobat, that send data in a form that can't be altered by the receiver, which is ideal for contracts or other sensitive information. Another great advancement in e-mail technology is the ease with which you can access your mail when travelling, anywhere in the world.
There are also companies that offer free e-mail accounts, like Gmail, that supply the service in the hope that you will be enticed by paid advertising that pops up when you log-in to check your mail. These types of e-mail accounts are terrific if you have members of the family that what their own personal addresses, rather than sharing yours, and when travelling (if your Internet Service Provider doesn't offer an easy-to-use retrieval service).
Increasingly however there has been an influx of nuisance e-mails - chain letters, unsolicited junk e-mail and offers of get-rich schemes. Beware of these, especially as they are just another variation on old pyramid-selling operations. Be wary of any e-mail with something like "Never have to worry about money again!" in the subject line, or a sender with an obscure e-mail address like firstname.lastname@example.org. If enough people ignore unsolicited mail, it may eventually just go away.