Check out example codes for "flutter margins". It will help you in understanding the concepts better.

Code Example 1

Container (
	// Even Margin On All Sides
    margin: EdgeInsets.all(10.0),
    // Symetric Margin
    margin: EdgeInsets.symmetric(vertical: 10.0, horizontal: 5.0),
    // Different Margin For All Sides
    margin: EdgeInsets.fromLTRB(1.0, 2.0, 3.0, 4.0);
    
    child: Child
    (
    	...
    ),
)

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