What is spam?

Spam is a term sometimes used generically to mean any email you do not want.  But the technical meaning of spam is much different.  It is an email message (or forum post) that is sent automatically by a computer.  The computer that sends the spam messages is usually "hijacked" by a "virus" or a program that is downloaded and run on your machine without you knowing it.

Spammers hijack pc's, millions of them in fact.  After your computer is hijacked your machine is used to send a message to others.  Not just one email message but millions. 

Some people have only found out about this when their internet provider cuts them off with a subsequent phone call or authorities show up at their home.  But these are extreme cases and most spammers avoid generating such publicity by not getting their hosts (you) in trouble. It is best left a secrete on your machine as long as possible.

Sometimes people hire spammers to generate sales for them.  At a rate of return in the range of 0.00001% these people can make thousands of dollars in one day or in a few hours if only a small rate buy from them.  This is illegal but it is very hard to track these people down since your pc is essentially sending the email for them. 

Why do you care? 

Hijacked pc's don't run perform very well when they are being used to distribute millions of messages.  Spam costs your internet provider a lot of money a cost which has to be passed on to you.  Spam also shuts down a lot of servers and costs businesses and consumers a lot of money directly.  I have repeatedly had to clean and restore hijacked pc's for clients and it cost them a fortune.  A lot of times they could have bought  a new pc or two or three for what they paid me to get their business running again.

Spammers sometimes operate in a locale that has not addressed the problem legally yet.  So if they are caught they can recover (pay a fine, escape) and get back into business as soon as possible.  If you are caught in most countries you will be prosecuted and sent to prison for launching spam campaigns.

What kills me is that someone actually buys something from a spam message.