We can all make things look complicated.
You: John, does "print" refer to: (1) putting ink on paper; (2) adding some data to an output buffer (possibly encoding it first) that will, when flushed, be pushed into an output stream that will probably result in its being stored in a file or displayed on a computer monitor, but is, in fact, highly unlikely to involve ink or paper?
DATA is not a standard feature of modern programming languages, but it's really not that strange in the grand scheme of things. There have been plenty of other languages that do provide equivalent features, right back to the good old 8-bit BASICs found in every techie home throughout the 1980s.
And, more to the point, __DATA__ is a pretty common feature in the Perl world. It's a standard tool in nearly all the test suites I've ever seen, both on CPAN and in proprietary internal code. I'd go so far as to say that if I was giving a job interview to someone who claimed to be an experienced Perl developer, but didn't have the faintest inkling that __DATA__ had a special meaning, then I'd fail them on the spot.