What is 'this.' keyword in JavaScript

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In JavaScript 'this' is an object and a reference to the current object that is used to get and to set properties of the current object.

Take for instance within a function;

const func = function (name){
    this.name = name
}

func.name instance property name is set to that of the first argument;

const inst = new func('duke')

inst.name
// returns duke

You can as well extend func to set name using 'this';

func.prototype.set = function(name){
    this.name = name
}

Running the previous instance with this set method;

inst.set('John')
// returns John

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