The email address is an important data point, and there’s more to it than just a simple string comparison.
Email addresses are used by many businesses as unique identifier, as part of the login credentials. This works well because as such, users remember their login name, it is unique meaning that there is no conflict between two users, users cannot create multiple accounts under their same address, and the email address is being asked for anyway.
However: two addresses may be different yet deliver into the same mailbox. This is good to know to prevent duplicate accounts, and is useful in search.
The address contains information about its users. To what entity it belongs (the domain name). And the local part often contains the person’s name. Again, useful in search.
Optimaize provides APIs to handle various aspects of email addresses in your application. These functionalities are an integral part of SearchCluster.