Responsive means your site or app can adjust itself to fit any screen—whether it’s a laptop, tablet, or phone. Basically, it makes sure everything looks good and works well no matter what device someone’s using. The layout shifts around automatically to match the screen size, so it’s always easy to use and nice to look at. These days, since so many people browse the web on their phones, having a responsive design is a must if you want more users and a better overall experience.