Email marketing gives you the opportunity to communicate with people who've opted-in to hearing your message. These could be former or future customers, depending on how skillful you are at converting casual visitors to your website (perhaps ones you paid for!) into subscribing to your emails.

Why is email marketing powerful?

Email marketing is free and reaches your customers alongside their important email. It allows you to stay at the top of their mind and reach a broad list of proven-interested people. This can be particularly powerful when you'd like to offer a special.

How does email marketing work?

There are two parts to email marketing: collecting users' email addresses, and writing relevant emails that draw their attention. Similar to attracting followers on social networks, you can offer incentives such as prizes or free samples in exchange for email addresses. Many times you can collect an email address as a side product of a purchase or reservation: just make sure the customer knows that they'll receive infrequent emails from you in addition!

Unlike social marketing, people generally expect email to contain non-trivial news or information. Specials, deals, and "of the month" clubs qualify; temporary changes in hours or new products don't.

How do you measure email marketing?

When you send a link in an email, make sure that it has the appropriate tracking parameters for google analytics. That will allow you to see how many people clicked on links in your email and what their subsequent interaction with your site was. Unfortunately (see challenges), it's rather difficult to track how many people opened your email but did not click on any of the links.

What are the challenges of email marketing?

Unfortunately, email marketing can be quite challenging. If your customers do not find your emails useful, they may ignore them completely or, even worse, mark them as spam. (This is particularly true if there is no easy/obvious way to unsubscribe). If you get a reputation for sending spam, your emails will be penalized for all users (ie, your emails will go to their spam boxes, which few actively monitor).

In terms of tracking the success of your emails, you are at the whim of the customer's email provider. If they choose not to download images automatically (or at all), you will not be able to track this rather-useful stat.