One of the most popular forms of advertising a business is email marketing. Email can be a powerful marketing tool, if you know what you're doing.

No one likes to have spam fill their inbox, and in the United States, spam is illegal, with the Federal Trade Commission going after major spammers. Rather than spamming millions of email addresses, build a list of customers and prospective customers, and market to them.

You can use your email as a marketing tool in a variety of ways. For example, you can create an ezine filled with valuable niche content that your list can actually use. Or, you can send out emails announcing your latest product or service. The key is to make your emails something your list wants and to ensure those emails are not marked as spam.

Email marketing can be somewhat of a challenge because of the prevalence of spam filters in email programs today.

The key to successfully promoting your business with email marketing is to ensure the emails you're sending out will not be flagged as spam. The best and easiest way to ensure you're not sending spam is to enlist the help of a service that scans emails to determine whether or not they will be flagged as spam.

To avoid having your email marked as spam, avoid such blacklisted words as 'buy now' and 'free'. But, even if you avoid such words that are considered spam, make sure you use a paid or free service like ezinecheck to ensure your emails are spam free.

In addition, remember that not everyone has high speed internet access. Therefore, if you're sending out HTML emails, your dialup customers may find the email download takes far too long and won't take the time to read your email. So, make sure your list has the choice between receiving HTML and plain text emails.

Email marketing can be extremely affective, but don't overdo it. Only email your list periodically. Once a week, every two weeks, or once a month. If you inundate email inboxes with emails, you're only going to annoy those people on your list.

Additionally, ensure you personalize each email by using the list member's name in the heading, and even in the body, of the email.

Finally, email marketing can be a hugely successful method of promotion, if you send directed emails only to those people who have given you permission to email them. The last thing you want is to establish a reputation as a spammer.