Puremessage not updating
It gives an overview over your emails in the currently opened mailbox. The information you see in the index is a list of emails, each with its number on the left, its flags (new email, important email, email that has been forwarded or replied to, tagged email, ...), the date when email was sent, its sender, the email size, and the subject.
Additionally, the index also shows thread hierarchies: when you reply to an email, and the other person replies back, you can see the other person's email in a "sub-tree" below.
Many commands (such as saving or copying a message to another folder) can be applied to a single message or a set of messages (so-called messages).
The help screen is meant to offer a quick help to the user.
It lists the current configuration of key bindings and their associated commands including a short description, and currently unbound functions that still need to be associated with a key binding (or alternatively, they can be called via the Mutt command prompt).
Mutt supports a rich config file syntax to make even complex configuration files readable and commentable.
Because Mutt allows for customizing almost all key bindings, there are so-called which can be executed manually (using the command line) or in macros.