What is the most famous invention ever?

Answer 1

# Haviland Carrier patented the centrifugal refrigeration machine. They called him "the father of cool # Hungarian journalist named Laszlo Biro invented the first ever ballpoint pen. # Joseph Woodland and Bernard Silver invented the barcode method of automatic identification and data collection # James Ritt and John Birch got a patent for inventing what they nicknamed the "incorruptible cashier." It was the first known working, mechanical cash register in existence.