Airplane cabins have cameras that are primarily used for safety and security reasons.
Cameras can be placed outside the cockpit so pilots are aware of what's going on outside their cockpit door.
Flight attendants can use cameras to view a cabin that might otherwise be obstructed from their seats.
It's not at all uncommon to see travelers taking pictures when aboard an airplane as the miracle of flight allows for some remarkable views of the planet.
But travelers might be surprised to know that there are times when cameras are watching them during their aerial journeys.
Many aircraft cabins are full of cameras that can be used for a variety of purposes, namely safety and security.
Here's why aircraft have - and sometimes need - cameras both inside the cabin and along their exteriors.
Cameras that show the exterior of an aircraft are primarily tools for pilots and are mostly installed on large aircraft to aid pilots as they maneuver around airports.
Airlines can opt to install exterior cameras on modern wide-body aircraft including but not limited to the Boeing 787 Dreamliner and Airbus A350 XWB that pilots can access through their cockpit display screens.
The cameras help pilots properly navigate taxiways, especially during tight turns with which larger aircraft may have a more difficult time maneuvering.
Cameras can be placed on the tail of aircraft as well as near the landing gear in the nose of the aircraft, and are essential equipment for behemoth aircraft including the Airbus A380.
Passengers also benefit from exterior cameras as they will often have access to them through their in-flight entertainment systems, giving them another option to look outside rather than through the aircraft windows.
Cameras primarily let passengers have the same view as their pilots on takeoff and landing, when the runway is directly ahead of the airplane.
Exterior cameras, however, often prove to be useless at high altitudes and while flying over water.
Top-down cameras can provide clearer images of the ground below but forward-facing cameras may just show blue skies and clouds.
But airplane cameras aren't always facing outward. Some are used to look inward to the passenger cabin of an aircraft as flight attendants need to have a way to view their passengers.
JetBlue Airways used cameras to solve a problem on one of its newest aircraft, the Airbus A321neoLR that's used on its flights between New York and London, as well as some flights between New York and Los Angeles.
See inside the first JetBlue plane with all-new Mint business class suites which are set to impress on upcoming flights to London
Flight attendants sitting in the jumpseat of the forward galley didn't initially have a clear line of sight throughout the Mint business class cabin that stretches as far as 12 rows back on some JetBlue aircraft.
The solution, to ensure that flight attendants could see their passengers during takeoff and landing, was a camera accessible through the flight attendant control panel.
There's no need for the cameras once the flight is in the air as flight attendants can keep an eye on their passengers while they work and move around the cabin.
I flew JetBlue's new London to New York route in Mint business class. It's a premium leisure traveler's dream but some kinks need to be ironed out.
Cameras also help maintain cockpit security by allowing pilots to see outside the cockpit door without having to open it, as doing so would jeopardize the security of the flight deck.
Cockpit cameras typically focus on the space immediately outside the cockpit door and not on the aircraft cabin.
Embraer's E195-E2 demonstration aircraft, for example, has the cockpit camera system set up to show potential customers.
I went onboard one of Embraer's newest yet worst-selling jets and can't understand why more airlines aren't buying it. See inside the Embraer E195-E2.
Pilots can easily identify themselves when returning from using the lavatory, for example.
Otherwise, only a small peephole lets pilots see through the reinforced cockpit door.
But not all aircraft have cockpit cameras as their installation is at the discretion of the airline.
On the inaugural flight of Breeze Airways in May, for example, the camera monitor in the cockpit was inoperable. Cameras are merely an additional layer of security of which not all airlines have to adopt.
Most onboard cameras are discreetly hidden and most travelers won't even realize that they are there.
But especially on aircraft that can seat around 500 people, including an Airbus A380, cameras help the flight and cabin crews maintain situational awareness during the flight.
Cameras can also be found on aircraft with no passengers at all.
Boeing 777 Freighter aircraft flying for Emirates' air cargo division, Emirates SkyCargo, have exterior and interior cameras that can be used to monitor cargo, including while it's being loaded and offloaded from the aircraft.
Pilots can view nearly the entire process without having to leave the comfort of the aircraft.
Travelers may also find cameras at their seats if flying on aircraft with seat-back entertainment displays.
Much like a tablet, some of the screens may have a forward-facing camera aimed directly at a passenger.
But, according to CNN, airlines seldom use these seat-back cameras and passengers shouldn't worry about having to be spied on.
Flight crews aren't constantly utilizing the cameras found on aircraft but they do help to fill the gaps when needed, especially as aircraft have grown in size over the year and incidents of in-flight violence have plagued the aviation industry.