Underscore prefix for property and method names in JavaScript

Question

Is the underscore prefix in JavaScript only a convention, like for example in Python private class methods are?

From the 2.7 Python documentation:

Answer 1

import/export is now doing the job with ES6. I still tend to prefix not exported functions with _ if most of my functions are exported.

If you export only a class (like in angular projects), it's not needed at all.

export class MyOpenClass{

    open(){
         doStuff()
         this._privateStuff()
         return close();
    }

    _privateStuff() { /* _ only as a convention */} 

}

function close(){ /*... this is really private... */ }