General topics on how do airplanes fly?

Airplane registration

In order for a civil airplane to be permitted to fly, it must be registered with a unique alphanumeric string that identifies it, similar to car registration. According to the Convention on International Aviation all airplanes must be registered with the national aviation authorities. 

Every airplane must have a proof of registration which comes in the form of registration certificate, and it required to have a registration plate displayed somewhere visible inside the cockpit.

Each country has its identification letter prior to the alphanumeric registration mark, for example USA is identified with letter N, while Lebanon is identified with the letters OD, France with the letter F, and UAE with A6.

To know more about the registration number and country codes, please visit wikipidia at: 

https://en.wikipedia.org/wiki/Aircraft_registration