Mail formats

MBOX

Mbox is a generic term for a family of related file formats in unix, used for holding collections of email messages.

mbox is 1 sigle file per hoofd folder , in plain text

mbox can be imported into Thunderbird using the import tool

EML

Used by many email clients including Novell GroupWise, Microsoft Outlook Express, Lotus notes, Windows Mail, Mozilla Thunderbird, and Postbox.
The files contain the ==email contents as plain text in MIME format==, containing the email header and body, including attachments in one or more of several formats.
- emlx
used by Apple Mail

other mail formats

• msg
  Used by Microsoft Office Outlook and OfficeLogic Groupware.
• mbx
  Used by Opera Mail, KMail, and Apple Mail based on the mbox format.

more deatils see https://en.wikipedia.org/wiki/Email#Filename_extensions