ken@tester:~> cd Desktop
ken@tester:~/Desktop> cd Downloads
ken@tester:~/Desktop/Downloads> cp /dev/hdc puppy.iso
cp: cannot stat `/dev/hdc': No such file or directory
ken@tester:~/Desktop/Downloads> dd if=/dev/cdrom of=puppy.iso
dd: opening `/dev/cdrom': No medium found
ken@tester:~/Desktop/Downloads>

ken@tester:~> cd Desktop
ken@tester:~/Desktop> cd Downloads
ken@tester:~/Desktop/Downloads> cp /dev/hdc puppy.iso
cp: cannot stat `/dev/hdc': No such file or directory
ken@tester:~/Desktop/Downloads> dd if=/dev/cdrom of=puppy.iso
dd: opening `/dev/cdrom': No medium found
ken@tester:~/Desktop/Downloads>