SPF (Sender Policy Framework) SPF is a protocol used to prevent spammers from sending messages on behalf of your domain. It allows you to specify which mail servers are permitted to send email on behalf of your domain by creating a specific SPF record in your domain's DNS settings.
DKIM (DomainKeys Identified Mail) DKIM adds a digital signature to your emails, which allows the recipient's mail server to verify that the email was indeed sent by you and that it hasn't been altered during transit. This is achieved by attaching a cryptographic signature to the email header.
DMARC (Domain-based Message Authentication, Reporting, and Conformance) DMARC builds on SPF and DKIM by providing a way for domain owners to publish policies on how to handle emails that fail these checks. It also provides a mechanism for receiving feedback about email authentication failures, helping you to monitor and improve your email security.
BIMI (Brand Indicators for Message Identification) BIMI is a relatively new standard that allows you to display your brand logo next to authenticated emails in the recipient's inbox. This not only enhances brand recognition but also signals to recipients that the email is genuine.