Image Format???

[micros50 <micros50 computer net>]

Several users have sent me mail asking about images that they have 
received attatched to email messages. These images seem to be of a type 
that I am not familiar. They carry the extension ".ART", for example 
"image1.ART". 

They can't seem to open them (view them) under common Linux utilities like
xv, zgv, etc. 

Is anyone familiar with this format?? Is this some format used by some 
Micro$$oft app?? Is there any Linux utility/program available that can 
either open and view this format, and/or convert it to another format 
which can be readilly opened by xv ??

Any help would really be appreciated. Thanx.

/John Hollister 
/micros50 computer net