file in malibox is readable format?

Hi,
Files coming to mailbox are in readable format?
Is there any special command to read these files.
suppose i have sent a file like this

              megh$mailx -s "mesg" [email]xyz@server.domain<file1.dat[/email]

can xyz directly read the file from his mailbox?

Greetings,
>Files coming to mailbox are in readable format?
Yes...
>can xyz directly read the file from his mailbox?
Yes, using mailx....