Q2591. What are the best practices for optimizing JavaScript bundle size?
Optimizing bundle size improves load times, reduces bandwidth usage, and enhances user experience, especially on slow networks. **1. Code splitting:** ```javascript // Sp...
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Q2592. What is JavaScript?
JavaScript is a programming language used to create interactive and dynamic web pages, as well as to create more complex applications on the client and server side.
Q2593. What is the difference between let, const, and var in JavaScript?
The var keyword is used for variable declaration in older versions of JavaScript, while let and const were introduced in ES6. Var has a function-level scope, while let an...
Q2594. How do you convert a string to a number in JavaScript?
In JavaScript, there are several methods to convert a string representation of a number into an actual numeric type, each with distinct edge case behaviors: ### 1. `Numbe...
Q2595. What are arrow functions in JavaScript?
Arrow functions are a shorthand syntax for writing function expressions in JavaScript. They use the `=>` syntax to separate the function parameters from the function body...
Q2596. What are first-class functions in JavaScript?
First-class functions means when functions in that language are treated like any other variable. This means that functions can be assigned to variables, passed as argumen...
Q2597. What is the scope chain in JavaScript?
The scope chain is how Javascript looks for variables. When looking for variables through the nested scope, the inner scope first looks at its own scope.
Q2598. What is a closure in JavaScript?
In JavaScript, a closure is created when a function is defined inside another function and the inner function is returned from the outer function. The inner function has ...
Q2599. What is the purpose of the "use strict" statement in JavaScript?
The "use strict" statement is used to enable strict mode in JavaScript, which helps to prevent common errors and make the code more secure. It prevents things like use of...
Q2600. What is the difference between synchronous and asynchronous code in JavaScript?
Synchronous code executes tasks in sequence and waits for each task to complete before moving on, while asynchronous code can execute multiple tasks simultaneously and do...