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docs/api/pointer-tracker.md

     Pointers in adjusted space are contained in normalized space, but unless the viewport is a square, one of their coordinates, x or y, will no longer range from -1 to +1. It will range from *-s* to *+s*, where *s = min(a, 1/a)*. In this expression, *a* is the aspect ratio of the viewport and *s* is less than or equal to 1.
 
     Selecting the adjusted space is useful for making sure that pointer speeds are equivalent in both axes and for preserving movement curves. Speeds are not equivalent and movement curves are not preserved by default because the normalized space is a square, whereas the viewport is a rectangle.
+
+    In summary: prefer the adjusted space when tracking movements.

docs/api/trackable-pointer.md

 
 `pointer.duration: number, read-only`
 
-The elapsed time, in seconds, since the tracking of this pointer began.
+The elapsed time, in seconds, since the tracking of this pointer began. You can check if this pointer represents a tap by comparing its duration to a threshold at the `"ended"` [phase](#phase). Example: `isTap = pointer.phase == "ended" && pointer.duration < 0.25`.
 
 ### movementLength
 
 
 `pointer.movementDuration: number, read-only`
 
-The total time, in seconds, in which this pointer has moved. You can get the average speed of motion, excluding the times in which this pointer has not moved, by calculating the ratio `movementLength / movementDuration`.
+The total time, in seconds, in which this pointer has moved. You can get the average speed of motion, excluding the times in which this pointer remained stationary, by calculating the ratio `movementLength / movementDuration`.
 
 ### isPrimary
 
 `pointer.isPrimary: boolean, read-only`
 
-Whether or not this is the primary pointer among all pointers of this [type](#type). A typical primary pointer is that of a finger that touches the screen when no other fingers are touching it.
+Whether or not this is the primary pointer among all pointers of this [kind](#kind). A typical primary pointer is that of a finger that touches the screen when no other fingers are touching it.
 
 ### kind
 
 `pointer.kind: string, read-only`
 
-The type of device that originated this pointer. Typically `"touch"`, `"mouse"` or `"pen"`.
+The kind of device that originated this pointer. Typically `"touch"`, `"mouse"` or `"pen"`.