To help explain the scope and approaches used for digital marketing working with the IDM in 2005 I developed a more (too?) detailed definition than the simple one at the start of this post to better scope it and show how digital marketing needs to be closely aligned to broader marketing objectives and activities and involves much more than SEO and inbound marketing. So this is the original definition from 2005 - how should it change now?
Email blasts are a great way to send bulk correspondence with businesses or consumers. Eblasts can contain special promotional information to customers or critical updates to other businesses. Sending ineffective or irrelevant emails to people will cause them to ignore future emails and can tarnish your company's reputation. Luckily, there are ways that you can optimize writing your e-blasts so that they captivate the largest audience possible. By using best practices to write and send your email and by evaluating the progress and effectiveness of them, you'll be able to reach a much wider customer base.
Buying email lists aren’t allowed by reputable email marketing services Email marketing services, including Constant Contact, do not allow you to use purchased lists. That’s because we are an email service provider that maintains a strong anti-spam policy to ensure that our customers are only sending emails to people who have expressed interest in receiving them. And that means refraining from buying an email list.
Particular groups of customers can be targeted or even individuals. Offering individual customers special deals on merchandise and/or services on the customer's birthday, for instance, is one example of email marketing personalization. (A restaurant might send an email to customers on their birthday offering 50% off an entree,) Email marketing helps a business develop and maintain a relationship with a customer over time that hopefully results in increased sales and increased customer loyalty. 
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