const Constants are block-scoped, much like variables declared using the let keyword. The value of a constant can't be changed through reassignment, and it can't be redeclared.
You could use const when, as you say, it will not be re-assigned and is constant. For example if you wanted to assign your birthday. Your birthday never changes so you could use it as a constant. But your age does change so that could be a variable. Show activity on this post.