Displaying Additional Index Information

  Choose Full Information...  from the Edit menu to display
  additional information about the selected messages.  The
  following information is displayed:

  -   The message number.

  -   The envelope (address information) of the message.

  -   The relative size of the message.  For ASCII messages the
      size is shown in records.  For non-ASCII messages, such
      as those with a DDIF format, the size is shown in blocks.

  -   The external ID if one exists.  External message IDs are
      assigned to non-ASCII files and to messages too large to
      be stored within the mail file.

  -   The attributes of the message, such as Replied if you
      replied to the message, Marked if you marked the
      message, New if you have not read the message, and
      the message type of non-ASCII messages, such as DDIF.

  Additional topics:

  *   Overview of Mail