You answer:

I recently had to deal with bimi while I was trying to set a DMARC, SPF and DKIM DNS records on my domain name. The main purpose of it is to provide a way for people to be confident that the emails they receive from e-commerce stores are actually legitimately from that store, and not from phishers or scammers. When you send an email from your e-commerce store, it's digitally signed using this protocol, so when your customers receive it, their mail client will show them an icon letting them know the email is legitimate.