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While I studied aviation, I got confused by these two words. Can anybody explain whether they're the same or not, and if not, what is the difference?

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For the simple case, yes. The threshold will be the end of the runway. The AIM has a graphic showing standard markings past the a normal threshold.

enter image description here

However, the airport operator may decide that aircraft should not land at the end of the runway. This may be temporary (perhaps for construction), or permanently (for obstacle clearance or noise abatement). In such cases the threshold is moved and marked away from the end of the runway. When permanent, this is called a displaced threshold and will reduce the landing distance available (LDA) to less than the length of the paved runway.

enter image description here

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  • $\begingroup$ A.k.a displaced threshold. There are also overrun areas with yellow arrows pointing towards the runway threshold $\endgroup$ – Jan Apr 8 at 6:37
  • $\begingroup$ I look at displaced thresholds the other way: the threshold is put where it needs to be for obstacle clearance, but if the land in front of it is also usable, why not make it available for takeoffs, which require more runway than landings do? $\endgroup$ – StephenS Apr 8 at 16:03
  • $\begingroup$ @StephenS In the case depicted in the lower image it is indeed allowed to take off using the section marked with white arrows. However, sometimes it is not allowed (for example if the runway can't handle the weight of aircraft). In this case the term used is "Overrun area" and the marking is yellow chevrons: en.wikipedia.org/wiki/Runway#Sections_of_a_runway $\endgroup$ – DeepSpace Apr 8 at 18:08

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