What is the meaning of the Ky Fan k-norm to be the bridge between sum and max norm

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In Matrix Analysis by Horn and Johnson (page 320 in 2nd Edition), the definition of the k-norm is as follow: $$\large \|x\|_{[k]} = |x_1| + \cdots\cdots + |x_k|,\text{ where } |x_1|\geq\cdots\geq|x_k|$$

And a property is as follow: $$\large \|\cdot\|_\infty = \|\cdot\|_{[1]}\leq\|\cdot\|_{[2]}\leq\cdots\leq\|\cdot\|_{[n]} = \|\cdot\|_1$$

Although I can verify this property , I am very confused.

$\|\cdot\|_\infty $ = max{ abs of the all elements} and $\|\cdot\|_1$ = {sum of all the elements}

How could they be equivalent? (Though they are equivalent through the proof) I think there is a gap. Any help is appreciable. Thanks!

P.S. You can also explain in matrix language.