what did standard deviation tell us?

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in my first course in Statistics when I took the measure of variation the first thing intoduced to me is :(The variance) which has this formula :

\begin{gather*} \sigma^2=\frac{1}{N}\sum_{i=1}^{n}(x_{i}-\mu)^2 \end{gather*}

and The variance tells us the average of squared distances from the mean, but the standard deviation is the square root of the variance given by this formula : \begin{gather*} \sigma=\sqrt{\frac{1}{N}\sum_{i=1}^{n}(x_{i}-\mu)^2} \end{gather*}

My question is : what did standard deviation tell us ? it takes only the square root of variance

I've searched online for the answer of my question but all the answers are like this :

Standard deviation tells us about the variability of values in a data set, It is a measure of dispersion

or like this

The standard deviation is the average amount of variability in your data set

but I don't understand How they came with these answers , all what i understand that is :standard deviation is just the square root of variance but i don't know what it really tell us