Direct mail is the ability to send text-based emails to a single constituent or groups of constituents using the Actions menu on a grid. It is most often used for sending quick messages like a board meeting reminder to your board members. You can learn more about the direct email feature in this article "Direct Emails".

Email marketing is for sending email campaigns for things like newsletters, announcements, invitations, and other communications where you wish to include colorful backgrounds, images, and links. 

• Email marketing can also track overall open and click rates, where direct mail can only track open rates for specific constituents. 
• Email marketing campaigns require an email list or lists and the use of the email template editor to create your message. 
• Email marketing campaigns also generate a unique URL for each campaign that you can share via social media or on your website.
• You can learn more about the steps involved in an email marketing campaign in this article "How do I create and send an email marketing campaign?"

Both email marketing and direct mail should only be sent from an email address using your verified domain name. You can learn more about verified sender domains in this article "Verification of DNS Settings".