HTML stands for HyperText Markup Language. It is the standard markup language used to create and structure content on the web. HTML elements are the building blocks of web pages, defining headings, paragraphs, links, images, and more.
CSS stands for Cascading Style Sheets. It is a stylesheet language used to describe the presentation of a document written in HTML. CSS controls layout, colors, fonts, spacing, and overall visual appearance of web pages.
JavaScript is a versatile programming language primarily used to add interactivity and dynamic behavior to web pages. It runs in the browser and can manipulate the DOM, handle events, make network requests, and much more. It is an essential technology of the modern web alongside HTML and CSS.
Responsive design is an approach to web development that ensures a website looks and functions well on a variety of devices and screen sizes, from desktop monitors to mobile phones. It typically involves flexible grids, fluid images, and CSS media queries to adapt the layout accordingly.