While it is very easy to distinguish between FA on one side, and TA and PA on the other, it is really difficult, if not impossible to distinguish between the latter 2.
For the sake of clarity let's assume that both pure TA and PA traders do not care for fundamentals at all. If they, do, they are not pure TA/PA traders.
Both make trading decisions based on what the price is doing at the moment, giving them probabilistic expectations on what is going to happen next.
So how we define what "at the moment" and what "next" means?
Is "at the moment" the current second, minute, hour, or day, or candlestic/bar?
Is the "next" the next second, minute, etc?
This is an important question, because PA and "naked" PA traders often pride saying that they exclusively care for what the price is doing "at the moment", and do not care for what price did historically. Many allege that both TA and indicators are about historical (therefore for them "irrelevant") price movements, and PA concerns only about "current" movements.
But even if we define "current" as buying when price is going up, and selling when price is going down, it is obvious that an element of comparison must be there: compared to what is it going up or down? Compared to historical price movement and levels, whatever that means: the last second(s), minute(s), hour(s), day(s) etc.
Momentary price alone is completely meaningless.
It gains its meaning, its possible interpretation useful for probabilistic expectations only through its relation to previous levels/movements, to its own historical context.
So the difference between TA and PA is neither in the timeframe (do you care for the "current" ticks/bars/seconds/minutes/years) nor in the relevance of historical data.
Nor can it lie within the use of charts, DOM etc. because all of these are merely visual representations of price data series.
Many cite the indicatorlessnes/nakedness/pureness of PA as opposed to the use of indicators by TA followers.
All indicators are merely representations of historical price movements/events/levels pertaining often to a higher timeframe, on the currently visualized timeframe.
Being that, ideally they can help to reduce the amount of charts etc. one has to observe at the same moment. They are also parts of PA, or at least of its context.
The problem with indicators is not their existence or use, but their abuse.
They can easily lead to an information overload, and distraction.
So the problem seems to me much more a problem of distraction and focus.
Obviously, how much information an individual is capable to process at the same time and amalgamate into a meaningful, useful information leading to reasonable probabilistic expectations, and how much information leads to overload and loss of focus, depends on the capacity of the individual.
It is obvious, that the optimum amount of information, that still does not cause an overload and loss of focus may lead to better trading decisions. May, but does not have necessarily to.
A lot still depends on the trader's psychological preparedness.
So I would suggest to rather distinguish between processable amount of information opposed to information overload, than between TA and PA.
