Everything[0] has a physical manifestation. A computer program has a physical manifestation on its storage medium.
[0]: Let's not argue about whether it makes sense to say that abstract concepts also have a physical manifestation. Programs are concrete expressions encoded on a physical medium (whether using magnets, electrical charges or even the position of mechanical switches).
[0]: Let's not argue about whether it makes sense to say that abstract concepts also have a physical manifestation. Programs are concrete expressions encoded on a physical medium (whether using magnets, electrical charges or even the position of mechanical switches).