Most people who have ever been passengers on a plane will have experienced a bit of turbulence.
For the fortunate ones, this might have amounted to a bit of a jolt and that rollercoaster ride feeling that you've left your stomach a few feet above its actual position.
But others have probably been put off flying by the sheer devastation turbulence can cause on a flight - upsetting drinks, causing luggage to fall out of overhead lockers and generally causing panic.
One airline pilot has taken to his website AskThePilot.com to dispel rumours about turbulence and put passengers' minds at rest.
Here's everything you need to know about turbulence according to Patrick Smith, author of Cockpit Confidential.
1. Pilots don't worry about it
Patrick explains: "Turbulence is an aggravating nuisance for everybody, including the crew, but it’s also, for lack of a better term, normal."
He adds that, for a pilot, it's more of a 'convenience issue' than a safety concern
"The pilots aren't worried about the wings falling off; they’re trying to keep their customers relaxed and everybody’s coffee where it belongs."
They will also slow down to a designated 'turbulence penetration speed' - but you won't notice it, because it's not that different to regular speed.
2. It's not going to cause the plane to crash
"It's easy to picture the airplane as a helpless dinghy in a stormy sea. Everything about it seems dangerous. Except that, in all but the rarest circumstances, it's not."
"For all intents and purposes, a plane cannot be flipped upside-down, thrown into a tailspin, or otherwise flung from the sky by even the mightiest gust or air pocket.
"Conditions might be annoying and uncomfortable, but the plane is not going to crash
"Planes themselves are engineered to take a remarkable amount of punishment, and they have to meet stress limits for both positive and negative G-loads."
3. How much does it affect the plane?
You might think, while you're sitting in your seat feeling sick and trying to hold on to your lunch, that the plane has dropped a few hundred feet in a matter of seconds.
But this isn't the case at all. According to Patrick, the plane will barely move from its designated flight path even in bad turbulence.
He recalls one case of a patch of 'rough air': "It was the kind of turbulence people tell their friends about. It came out of nowhere and lasted several minutes, and was bad enough to knock over carts in the galleys."
Patrick says he watched the altitude meter and saw that the plane didn't move more than 40 feet either way. What's more, the direction of the plane didn't change at all - as the technology on the plane automatically corrects the route.
4. Can they predict turbulence?
Patrick explains they have many different ways to predict turbulence before it happens - from weather charts to radar.
Looking at clouds can help, as he points out that the large cumulus clouds with 'anvil-like' tops can point to rough pockets of air which pilots will stay clear of.
And flying over mountain ranges or jet stream boundaries can create a bumpy ride.
But he also says sometimes "you just don't know".
So next time you're experiencing turbulence on a plane, remember Patrick's words and be assured that in most cases, pilots are more worried about you spilling your coffee than crashing the plane.