MailChimp is marketing and email tool that we have integrated into our basic template offering. You can connect your MailChimp account with our backend by entering your MailChimp Audience ID. The system will then add users when they register an account and update their status in a 24h interval. Read more about the information that is added to MailChimp here.
Mandrill is a part of MailChimp and is used to send transactional emails. You can design and set up the emails in Mandrill. Then you need to add the slug name in the console to connect the two systems. Depending on the settings the email will be triggered when a certain event happens. You can find a list with automated emails that are currently supported here.
If you are looking for inspiration we can send you some templates.