Three windows on one day. Each session builds levels the next one uses, and the only way to see that is to look at all three on the same chart.
A session is a time window — Not a pattern and not a strategy. It is a stretch of the clock with its own character, and its high and low are levels like any other.
They are related — Asia builds, London takes one side of it, New York delivers. Reading one session without the other two is reading a third of the day.
Switch between them — The buttons above show the same day from each session's point of view — the levels do not change, only which window you are looking through.