Email - this is a professional & secure way to communicate with person, client, companies etc. If you have professional domain you must create professional mail of your domain name.
there are 12 types business Emails use
1 - Referral Emails
2 - Cart abandonment Emails
3 - Welcome Emails
4 - Announcement Emails
5 - Promotional Emails
6 - Newsletter Emails
7 - Transaction Emails
8 - Testimonials Emails
9 - Blog post Emails
10 - Client case study Emails
11 - Milestone Emails
12 - Lead-nuturing Emails