Am I the only one that already programs in text files? I know that's maybe being pedantic, but I'm not actually clear how the author's conception of programming

Am I the only one that already programs in text files? I know that's maybe being pedantic, but I'm not actually clear how the author's conception of programming in a text file differs from the normal way you'd write code (to be fair, the rest of the article didn't make much sense either).