Normalization means in standard deviation

in Matlab By default, the standard deviation is normalized by N-1, where N is the number of observations.in different places Normalization and observation is given different.so here what the normalization and observation mean?also what is the proper and exact method to find the normalization? …

[John D'Errico]

We could write a small book on it. In fact, people have done so already, in any number of basic texts on statistics.

https://en.wikipedia.org/wiki/Standard_deviation