If you’re a business owner and you want to market your product or service, the first thing you’ll ask yourself is how to reach your target audience. On the top of your list should be email marketing. In essence, email marketing is the sending of promotional messages via email. It’s the oldest digital marketing strategy around, yet it delivers one of the highest ROIs. Here’s what you need to know about email marketing so that you can use this powerful tool to help grow your business:

Email marketing is used to build brand awareness and has two main purposes. In the first instance, you would send emails to prospective customers with the intention of acquiring new business or encouraging people to buy something. The email might include an announcement or special offer enticing the user to take immediate action.

In the second instance, emails are used for retention purposes – to maintain relationships with existing customers and encourage repeat business. This type of regular email usually takes the form of an email newsletter. It should include valuable, interesting content for your customers to read, not just a promotional message.

In advertising lingo, email marketing falls under the umbrella of direct marketing. This means it is a form of advertising geared towards a target audience in a way that can be measured. For example, if you’re sending out bulk emails, how many people clicked on a link, made a phone call, or bought a product online after reading your mail? This is called the “response rate” and it’s a valuable metric used to measure the success of your marketing campaign. Email marketing is akin to sending people direct mail in the post, sending a print newsletter, or placing an advertisement in a subscription magazine or newspaper. There is one important difference, however, and that is the issue of permission.

Permission marketing is another term you’ll hear mentioned in connection with email marketing. This form of advertising requires that the prospective customer has given explicit permission for the business to contact them. For example, a customer has subscribed to receive an email newsletter. It differs from traditional advertising that interrupts whatever you’re doing to capture your attention, like a TV commercial. In the permission model, a customer has volunteered their attention by agreeing to learn more about a company and its products.

So these are the two pillars that make email marketing so successful. One, the fact that you can measure the results of your campaign, and two, the fact that you can target your message at a group of consumers who are interested in your product. This means that your budget is used more efficiently because offers are only sent to people that are actually interested in the product.