According to [git name-rev doc](https://git-scm.com/docs/git-name-rev) , 

> 
> Finds symbolic names suitable for human digestion for revisions given
>  in any format parsable by git rev-parse.
> 
> 
> 

But I could not understand this. What is the use of this command ? How is it different from [git describe](https://git-scm.com/docs/git-describe#git-describe---all) command ? I think that **both also does the same thing** - give a SHA1 Id , gives us back the nearest reference name to it ?