The source data can be a raw block device or more likely a local file. It doesn’t matter as either way the kernel is just reading blocks of bytes.
Not really tbh. I haven't used a CD in my adult life. I remember "burning a CD" was a thing and that's about it.
I was born in 1991 and I haven't used one since I was in 9th grade and made a girl a 'mix tape'.
The source data can be a raw block device or more likely a local file. It doesn’t matter as either way the kernel is just reading blocks of bytes.