How does JS understand props parameter as object in any function (react.js)?

While i am studying react.js, i noticed that any function i wrote and then give it any parameter name, javascript will understand this parameter as object type

Like this :

function Somthing(some){
    return (
        <div>
            Hello, friends{console.log(some)}
        </div> 
    ) 
}

expprt default Something

Then console.log(some) will give me “Object{}” type without assigning to it any object

So my question, How can i do this concept in vanilla javascript and how does javascript understand it?