About

A mail delivery agent (MDA) ¹⁾ is a local process that is responsible for the local delivery (reception) of e-mail messages to a mailbox

It's also known as:

• message delivery agent (MDA)
• local delivery agent (LDA)

An MDA gets normally the messages from an Mail Exchange (Smtp Server) and delivers them to:

• a mailbox (real or virtual).
• any other destination that it supports

List

• Dovecot LDA
• wiki/Maildrop (https://wiki.dovecot.org/maildrop)