A Dynamic List is constantly updated depending on whether specific criteria is met, such as a contact property or the last time a user has clicked on an email. Whenever a record meets this criteria, they will be added to the list. Alternatively, if they don’t meet the criteria anymore, they will be removed. This is why dynamic lists are, well… dynamic. What’s best, everything happens automatically.
A Static List consists of members who are added manually or through an import. The list members will not change unless you manually add or remove them.