What are the
The different types
Make no mistake about it, email marketing is possibly THE most effective way to increase revenue. Especially for an ecommerce website. If you have a database of customers (that have opted into marketing emails adhering to GDPR regulations) then you can can start cashing in on that list.
Email marketing companies like Mailchimp, Klavyio and Dot Mailer will charge a monthly fee to use their services but the returns you should see from this can be in excess of 50% ROI if you do it properly.
A few years ago it might have been acceptable to send out the same email to your entire database however with advances in technology from email marketing companies you are able to segment out your customers.
Perhaps you have an offer on men's jackets. It would be more effective to only send this to men rather than women who have perhaps looked at jackets on your website before. You can create segments based on almost any information you can think of, geographical location, past purchases, gender and even mood!