Laurence Svekis

JavaScript promises are objects used for handling asynchronous operations. They represent the eventual completion (or failure) of an asynchronous operation and allow you to write more readable and maintainable asynchronous code. Promises work based on the concept of “callbacks.” Traditionally, callbacks were used to handle asynchronous operations, but they can result in callback hell and … Read more

What is the difference between == and === operators? In JavaScript, the == (loose equality) and === (strict equality) operators are used for comparison, but they behave differently in terms of how they handle type coercion and equality checks. Here’s a detailed explanation of the differences between these operators: Loose Equality (==) Operator: The == … Read more

Explain the event delegation in JavaScript. Event delegation is a technique in JavaScript where instead of attaching an event handler to each individual element, you attach a single event handler to a parent element and handle the events of its child elements through event bubbling. This approach has several benefits, such as improved performance, reduced … Read more

What is hoisting in JavaScript? Hoisting is a JavaScript behavior where variable and function declarations are moved to the top of their containing scope during the compilation phase, before the code is executed. This means that regardless of where variables and functions are declared in the code, they are treated as if they were declared … Read more

What are the differences between var, let, and const? In JavaScript, var, let, and const are used to declare variables, but they have different scoping rules and behaviors. Here’s a detailed explanation of the differences between them: var: Variables declared with var are function-scoped or globally-scoped. They are hoisted to the top of their scope, … Read more

In JavaScript, null and undefined are both special values that represent the absence of a value. However, they have different use cases and behaviors. Here’s a detailed explanation of the difference between null and undefined: undefined: undefined is a primitive value in JavaScript. It is used to indicate the absence of an assigned value to … Read more

What are the different data types in JavaScript? JavaScript has several built-in data types that are used to represent different kinds of values. Here are the different data types in JavaScript: Number:  Represents numeric values. It can be an integer or a floating-point number. For example: var age = 25; var temperature = 98.6; String:  … Read more