A JavaScript Calculator is a simple interactive application built using HTML, CSS, and JavaScript to perform basic mathematical operations like addition, subtraction, multiplication, and division. It involves creating a user interface with buttons for digits, operations, and a display area using HTML and CSS. JavaScript handles the functionality, such as capturing button clicks, parsing input values, and performing calculations. A common approach is to use event listeners for button clicks and apply arithmetic operations dynamically. This type of project helps beginners practice DOM manipulation, event handling, and basic programming logic in JavaScript. Advanced calculators can include features like memory functions or scientific operations.