DKIM, short for DomainKeys Identified Mail, serves as an email verification technique. Its primary purpose is to empower the recipient's server to authenticate the legitimacy of an email. This is achieved through the inclusion of a digital signature within the email headers, a signature that's created using a private key linked to the sender's domain. For validation, the recipient's server relies on the public key readily available in the domain's DNS records. In essence, DKIM serves as a guardian against email impersonation, guaranteeing that the email indeed originates from the purported domain.