OK, sorry, I will try to be a bit clearer.

The following code will work, and successfully loads the image stored in an
image file into a Bitmap:

Bitmap^ image_bm = gcnew Bitmap( "image.JPG" ) ;

and this works as well:

Bitmap^ image_bm = gcnew Bitmap( "image.BMP" ) ;

but this DOESN'T work:

Bitmap^ image_bm = gcnew Bitmap( "image.TXT" ) ;

Thus, I know the language supports READING both JPG and BMP, and seems to do
so on every computer, thus it appears to accept these particular image file
formats natively (without having to install anything first).

What I'm interested in knowing is which OTHER image formats does this work
with? Equivalently, for which extensions .XYZ will the following also work:

Bitmap^ image_bm = gcnew Bitmap( "image.XYZ" ) ;

[==Peter=]