You ride on airplanes all the time, but how much do you really know about them? Considering that planes are constantly evolving, it's hard to know everything that goes on behind the scenes. There are a few things that I do know about them that the majority of passengers hardly give a second thought to.

If you're looking to demystify planes a little, or find comfort in knowledge like I do, then here are a few facts about flying and airplanes that you probably didn't know.

1. Flying dehydrates you.

On your previous flights, you might've noticed that you're thirstier than normal. Maybe your eyes and hands also feel dry. There's a reason for that.

The oxygen on a plane at takeoff rapidly decreases because everyone on the plane is constantly breathing. Carbon dioxide replaces the oxygen. To have the fresh oxygen you need to survive, the plane circulates fresh air from outside the plane while also sending the old air outside.

When you're in the air at such a high altitude, the only available oxygen that planes can circulate in has 10-20 percent relative humidity (your home likely has relative humidity in the 45-65 percent range). The dry air dehydrates you because it sucks 8 ounces of water out of your body per hour. While you might not notice a substantial difference on a short connecting flight, you'll certainly feel it on a long-haul flight.

Because of the dry air, your throat and nose won't have enough moisture to trap germs that may enter your airway. You'll be more prone to sickness if you don't stay hydrated. That is why it is recommended to drink water. I also like to carry eye drops and nasal spray.

2. Knowing where the safest place to sit is.

In a scenario where the plane is crashing head first, the middle seat in the back of the plane has the lowest fatality rate. According to a TIME study, 17 plane crashes between 1985 to 2000 with both fatalities and survivors were studied. Of their analysis, they found that the fatality rate for the back third of the plane was 32 percent and for the middle and front where 39 percent and 38 percent, respectively.

Their research also showed that the middle seat in the back had a 28% fatality rate while the aisle seat in the middle had a 44 percent fatality rate. Though these numbers may be frightening and reassuring at the same time, I want to assure you that while popular in the movies, plane crashes in real life are extremely rare.

3. Your delay might not be where you think it is.

I like to know the weather so I can prepare for any possible delays. However, I can't prevent all delays, mainly because delays aren't always due to weather issues. Though you might think that's where the weather is bad at, sometimes it's the cities in between your destination that are causing the problem.

4. Your phone may be interfering with the plane more than you know.

Though it's politely asked of you to put your cellphone and other electronic devices on airplane mode, there are always a few people who don't listen. Turning your cellphone and other electronics off when asked, is the polite thing to do. If you and a few other people are all on your phones, it can cause the pilot to miss clearance or have false readings.

5. Flight attendants are trained to protect you.

Even though flight attendants serve you drinks and snacks, they went through rigorous training to ensure that they can protect you in life-and-death situations. They go through up to 12 weeks of training to know the safety requirements and guidelines issued by regulatory companies.

When they complete their training, they know how to use all the safety equipment on board. They also know how to administer CPR and EpiPens, use defibrillators, stop nosebleeds, deliver babies, put out fires, and remain calm in the event of an evacuation in a high-stress environment.  

6. You're less likely to experience turbulence on a morning flight.

Although there's no way to guarantee you won't experience turbulence, you can pick flights that have less turbulent air. The sun's uneven heating of the ground causes for more turbulent air in the afternoon. Since the sun is just coming up in the morning, you'll experience a less bumpy ride. Sitting in the middle of the plane also minimizes the effects of turbulence.

7. Storing your laptop is for your own safety.

Although it may seem inconvenient to have to store your laptop during takeoff and landing, it's for your own safety. A laptop moving hundreds of miles per hour at a tilt is a dangerous safety hazard. Put your laptop away for your own safety as well as for those around you.