Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?

Question

Does javascript use immutable or mutable strings? Do I need a \"string builder\"?

Answer 1

Performance tip:

If you have to concatenate large strings, put the string parts into an array and use the Array.Join() method to get the overall string. This can be many times faster for concatenating a large number of strings.

There is no StringBuilder in JavaScript.