What is the difference between MX and spark?

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1

I read many article but i am still confused. Could any one tell me what is the
difference between MX and spark? If you try to explain with example that will
be good for me.

2

From Adobe Help Spark and MX components

…
The main differences between Spark and MX components are how you use CSS styles with the components and how you skin them. For the container components, there are additional differences about how the containers perform layout.
…

What confuses you?