Margin is the space outside the border of an element, creating distance between it and other elements. Padding is the space inside the border, creating distance between the content and the border itself.
In the first box, the margin of 40px pushes it away from surrounding elements. In the second box, the padding of 50px increases the space between the text and the border, making the content area larger.
Understanding the difference between margin and padding is crucial for effective web design and layout.