Automation Lite is an email or series of emails that are scheduled to be sent to your contacts over a specified period of days. An Automation can have multiple emails.
Automations are scheduled based upon the subscription date of each of your contacts. When you create your Automation, you can specify how many days after the subscription date to send a particular message.
For example, if you create an Automation email, you can set that email to be sent on day 0. This means that the contact will receive the message on the same day that they are subscribed to the list. If you set a message for day 5, the contact will receive the message 5 days after they subscribe to the list.
Note: The Automation will send emails to the newer contacts in a list. If contacts are imported to a list which has an active automation, the newer contacts will receive the automation emails.