List syncing is the process of linking your email list with a third party platform, such as a CRM or social media advertising tool. This allows for more streamlined and efficient marketing efforts, as all of your contacts are in one central location. Not only does list syncing save time by eliminating the need to manually input contact information, it also helps ensure that your list remains up-to-date and accurate.

There are four types of List Syncing: One-way, Two-way, Three-way, and Four-way.

One-way syncing means that changes made to the master list will be reflected on the slave list, but not vice versa.

Two-way syncing means that changes made to either the master or slave list will be reflected on both lists.

Three-way syncing means that changes made to the master list will be reflected on the slave list, and vice versa. However, if there are conflicting entries on both lists (for example, two different people adding different phone numbers for the same contact), then the most recent entry will take precedence.

Four-way syncing is like two-way syncing, except that it also takes into account any changes made to the lists while they were not connected. For example, if you add a new contact to your phone while it is not connected to your computer, and then later connect the two and sync them, the new contact will be added to your computer's address book.