gulp. Why is a callback needed in a task?

Question

Building projects

Sometimes in gulpfile I meet such a construction:

gulp.task("build", function(cb) {
  run(
    "clean",
    "copy",
    "style",
    "images",
    "js",
    cb
  );
});

Why is a callback needed here? In what situations does it apply?

Answer 1

Gulp allows you to chain tasks into dependency chains (before task A, you need to execute B), the callback tells gulp that the task is completed