because you walk up and down the runway doing all sorts of pose.
i am improving this answer. the answer above mine is stupid. it clearly says the category is in airports. okay, so if a runway is active it is used for takeoffs and landings. (not much of an answer though)
If an aircraft is on it, or about to land, a runway is active.
active runways taxiways
visual runways, non-precision instrument runways, and precision instrument runways
There are no paved runways in Antarctica. Airplanes land on skis, not wheels, on runways of ice.
By the lights and roads.
Vietnam has four runways
there are 5 runways.
At an airport with a control tower already have taxi clearance to cross all runways or get clearance from ATC to cross the runway. :)
Honolulu International Airport has six runways.
Because they are
ahmedabad airport (VAAH) has one runway vectored for take off and landings at 23 and 05. The ILS is active only on runway 23.
There are 5 runways at Toronto Pearson International.
because there are plenty of poor nations in africa, and paved runways costs money. On top of the the climate and soil conditions are favourable for keeping unpaved runways operational.