When taking off or when buttering on the runway, you may have noticed those different types of thresholds and the very end or beginning of the runway.
The first one is a “Pre threshold Area” which is not meant for aircraft movement. That means that you cannot stop on this part of the runway, taxi or take off.
The second threshold is also a “Pre threshold area” that is fit for aircraft movement as a stop way only. That means that you are able to line up and wait on this part of the runway, but not take off or taxi on it.
The third one is a “Permanently Displaced Threshold” fit for aircraft movement. This part reduces the stopping distance of the runway. But can be used for taxiing, or taking off.
And the last one is a “Temporarily Displaced Threshold” For 6 months or less. It has the same usage as the third threshold. But it’s going to stay there for less than 6 months.