In this guide
Why “area” is often better than “line”How the labels are usedObjective measurements around a subjective levelAvoid false precisionWhy “area” is often better than “line”
Highs and lows may cluster without matching exactly. A user may therefore draw a zone around several nearby values rather than a one-pixel line. The chosen width is part of the method and should be disclosed if calculations depend on it.
How the labels are used
Resistance generally refers to a reference area above a current value; support generally refers to one below it. If a value moves through the area, chart users may change how they describe the same location. The label reflects context, not an intrinsic property of the number.
Objective measurements around a subjective level
Once you choose a level, distance to it can be calculated exactly. The subjective step is choosing the level itself. Separating those steps is useful because it prevents a precise-looking percentage from hiding an imprecise assumption.
Avoid false precision
If a level was visually selected from a broad zone, reporting “resistance is exactly 100.0000” creates more precision than the method supports. Educational tools should preserve the precision of the inputs rather than imply certainty.