Even before someone thought up a box to carry stuff in, ancient travellers took a large cloth, flung things inside and tied the ends into a knot. This was called the potli here, elsewhere, the bindle, and was carried under the arm or at the end of a stick. Lakshman is said to have carried one.

&Oumltzi the Iceman, the well-preserved natural mummy dating back to 3,300 BCE, was found in the Alps two decades ago. He carried items that told a comprehensive story of his time among them was a wood-ribbed backpack with a leather bag.

The travelling chest, a tweak on the storage trunk, must be the first genuine precursor to the suitcase. Various woods were used, and covered with an array of oil-treated hide like deer, horse and cowhide.

&ldquoNo one&rsquos going to pull a suitcase on the end of a strap.&rdquo In 1970, Bernard Sadow had trouble persuading people to accept his concept of luggage with wheels. His four-wheeled bags were improved by a pilot Robert Plath in 1987, and that&rsquos how the two-wheels-with-telescoping-handles came to be.

Hop, as they say, is still in beta. But the robotic sensor-equipped bag promises to respond to the Bluetooth signal on your phone and follow you about. If the phone loses signal, it&rsquoll vibrate to tip you off and Hop&hellip well, it locks itself in place.