What is the significance of a firearm's 'rifling'?

The significance of a firearm's rifling lies in its ability to impart spin to the bullet as it travels down the barrel. This spin stabilizes the bullet in flight, enhancing its accuracy and range. The grooves and lands created by the rifling engage with the bullet, causing it to rotate. A spinning bullet is less susceptible to factors like wind drift and other external elements, allowing for a more predictable trajectory. This principle is crucial for effective aiming and hitting a target accurately, making rifling a fundamental feature in the design of most modern firearms.