One of the great advantages of relative units like the em unit is that they can make your page , allowing the page to be rendered the same way no matter what font size is used by the browser.

Flexible

Explanation:

The em unit is flexible since ot does not represent any specific pixel measurement.

relative units like the em unit can make pages FLEXIBLE and allowing pages to be rendered same way irrespective of font size

Explanation:

A relative unit obtains size from somewhere else. Relative units include - "em", "ch", "rem" and "ex". They are font - relative lengths. Making use of relative value entails things scaling up or down according to another value elsewhere.

For Example, a box inside the viewport that has width of 60% will continuously remain 60% of the available width, irrespective of the device being used. i.e whether a phone is being used or the image is being rendered on a high resolution display.

Let us assume that there's an extra box in the former box that has a width of 40%, it then assumes 40% of the width of the parent element and never that of viewport.

So, relative units generally encourage flexibility on pages and allowing the pages to render image the same way irrespective of the browser's font size.

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