Difference between Simple Present and Present Continuous

We use the present simple to talk abut:
a) routines. e.g.
I go to the swimming pool every week.
They play football at the weekend.
b) facts (things that are always true). e.g.
He lives in Tokyo
It always rains in Manchester.
But we use the Present Continuous to talk about "now" and temporary events, also we use the present continuos to talk about plans and arrangements in the future which are sure ti happen.
Often there's a definitive time and /or place for arranfements. e.g.
I'm catching the 6 pm train tomorrow.
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