Howard Slutsken from CNN explains in simple terms how the hundreds of daily international flights are routed across the North Atlantic.

With the recent introduction of advanced navigation equipment and procedures, aircraft on the OTS cruise five minutes' flying time behind the preceding plane, which is about 40 miles. Laterally, there's a 25-mile separation from the closest plane on either side, and a 1,000-foot safety zone above and below.

The video below beautifully illustrates the concept of layering and staggering the air traffic across the Atlantic.