To prevent illegal and dangerous activities, like smuggling of drug/weapons/stolen goods, to make sure no one is carrying explosives or weapons that could be used to hijack a plane. Also to prevent damage to people if there is a fight or a scene of some kind.
So over-all they are there to protect the every-day passenger.
Security checks are often legislated by a government, or demanded by government security. The airlines often have little choice in the level of security checks their customers are subjected to.
because people could have guns or alcohol or drugs in their luggage.
As major transportation hubs for both passengers and freight, airports greatly increase the flow of the local economy.
For coming to BD and fly from BD
i think Washington Airport
Not all airports are international airports, some are domestic airports.
So you could travel around the world to meet your family or just for a simple vacation. That's what I think :)
to know if it is clear for the planes to go by: Katrina
Oklahoma has many airports. The most important (not necessarily in order) are Will Rogers World Airport in Oklahoma City, Tulsa International in Tulsa, Wiley Post Airport, also in OK City and Stillwater Regional Airport.
There are three most important ones, located in Taipei, taichung, and Kaoshiung. There are others but its smaller and less important.
so we can get to difrent continents
With very few exceptions, airports are owned by their Governments. Some airports, normally smaller ones, are privately owned. The income from these larger airports goes to their respective Governments. Millions are made each year on landing fees and rental spaces from these airports. The airports are also able to bring in billions in income to hotels and local businesses.
They are usually only in International Airports as they are to stop drugs going into countries so you should be fairly safe if you are flying domestically.
the volcano became active
there are 47 airports in England there are 47 airports in England