What the user sees takes place in a browser and involves design and front-end development. Design defines a website’s colors, layout, font, and images—all the stuff that goes into a website’s branding and usability—and requires tools like Photoshop, Illustrator, Fireworks, and Sketch.
Using coding languages like HTML, CSS, and Javascript to implement that design is called front-end development. These languages make it possible for users to interact with buttons, images, text, contact forms, and navigation menus. And they’re integral to responsive and adaptive design.