In JavaScript, We can create an empty object using curly braces {} and the Object constructor....

To check if a value is a Promise in JavaScript, we can use the instanceof operator. Promises are a specific type of object, and this operator allows you to check if an object is an instance of a particular class or constructor function. so we will use this to check whether the given value is a promise or not....

In JavaScript, `e.target` refers to the event target of a user interaction, typically within an event handler function. It represents the DOM element upon which the event occurred. For instance, in an event listener for a button click, if the user clicks the button, `e.target` would point to that specific button element. This property is often used to access or manipulate the properties of the triggering element. It’s crucial for handling dynamic content or multiple similar elements where identifying the specific element interacting with the user is necessary. Understanding `e.target` is particularly valuable when implementing responsive and interactive web applications, as it allows developers to tailor responses based on the specific UI element involved in the user’s action. This property is commonly employed in conjunction with various DOM manipulation techniques for creating more dynamic and user-friendly interfaces....

In JavaScript, you can create an empty Map using the Map constructor. whenever we initialize any map it is empty at first and we need to declare the key-value pair inside the map constructor to construct the map having values....

In JavaScript, you can concatenate two variables (combine their values into a single string) using the + operator....

The Temporal Dead Zone (TDZ) is a concept in JavaScript that relates to the hoisting of the variables and the visibility of variables declared with let and const. In the TDZ, a variable exists but it cannot be accessed until it is not declared. This prevents the variable from being used or accessed before a value is assigned to it....

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In JavaScript, you can iterate over the elements of a Set using various methods, such as the forEach() method, the for...of loop, or by converting the Set to an array and using array iteration methods....

To check the size (number of key-value pairs) of a Map in JavaScript, you can use the size property. The size property is a property of the Map object that returns the number of elements in the Map....

In JavaScript, the event loop plays an important role in managing asynchronous operations and ensures the non-blocking behavior of the language. JavaScript is single-threaded, meaning it processes one task at a time and an event loop helps to handle asynchronous tasks efficiently. When an asynchronous operation, like a setTimeout callback or a user event, is initiated, it gets delegated to the browser’s APIs, allowing the main thread to remain unblocked. Once the operation is complete, a callback function is placed in the callback queue....

When you try to add a duplicate value to a Set in JavaScript using the add() method, the Set ignores the duplicate value. Sets are designed to store unique values only, and adding a value that is already present in the Set does not result in duplicates....

Callback hell is also known as the “pyramid of doom,”...