Anyone who has watched old NFL film highlights has witnessed the majesty of a spiraling football in full flight, soaring as though being propelled by the trumpets playing on the soundtrack. It spins through the air for what seems like forever, then the camera pulls back to reveal a speedy receiver intersecting with the descending ball for a touchdown.

While baseballs, basketballs, and even soccer balls can be hurled a good distance, nothing looks like a football when launched by a capable quarterback. In fact, no other ball looks quite like a football, period, in flight or at rest. So how did the centerpiece of America’s favorite sport take shape?

Football is one of several similar sports — soccer and rugby, among others — to diverge during the late 1800s. Lacking modern technology, they were played with the inflated bladders of pigs. That’s why “pigskin” remains one of football’s nicknames.

Early footballs were not quite round, and a watermelon-like shape was accentuated once the bladders were given a protective leather covering and tied closed with laces. But as the game evolved, so did the ball. Pig bladders gave way to rubber, while the ball became longer, narrower, and easier to grip and throw with one hand.

The current, prolate-spheroid shape has been around since the 1930s, and Wilson Sporting Goods has manufactured NFL game balls since 1941. They continue to be handcrafted by Wilson at an Ohio factory.

Four cowhide panels, each in somewhat of a diamond shape, are sewn together, inside out, leaving a gap. The panels are turned right side out through the gap; the rubber bladder is inserted; and the gap is sealed with the ball’s familiar laces.

At this point, the laces are technically unnecessary — the ball could be completely stitched. They are kept mostly for tradition, but gripping the laces helps quarterbacks sling a football with that elegant, spiral rotation.

The next time a football is tossed — in the backyard, at a tailgate party, or in front of 80,000 fans on a Saturday afternoon — admire its beautiful revolutions … and evolution, from the pigskin of yesterday to the “pigskin” of today.