It has two front chainrings and ten cogs in the rear. A 3x9 has three front chainrings and nine cogs in the rear. Although bikes used to have all types of drivetrains with 5, 6, 7, or other numbers of rear cogs, were going to start our discussion with 9-speed systems.
Neil Sedaka has a long and distinguished career as a pop singer, songwriter, and pianist. His many hits include Breaking Up Is Hard To Do (1962, 1975 slower remake), Laughter In The Rain (1975), and Bad Blood (1975).
OK, Neil Diamond is an easy target for parody -- voice straight outta Brooklyn, bespangled shirt straight outta Vegas. But this ex-Brill Building tunesmith crafted a batch of excellent songs during the 1960s (hits such as Solitary Man for himself and I'm a Believer for the Monkees) before emerging as a stadium superstar.