Cascading Style Sheets, known as CSS, is like the decorator of a website. It's used to make web pages look nice and stylish. Imagine HTML as the structure of a house – it builds the walls and puts everything in place. Then, CSS comes in to paint the walls, add curtains, and arrange furniture. In website terms, CSS changes the colors, adjusts the size of text, and decides where things go on the page. It works hand-in-hand with HTML, which is the basic language used to create a website. CSS makes sure that everything on a webpage looks good, whether you're looking at it on a computer, a phone, or a tablet. With CSS, designers can make websites look really attractive and easy to use, which makes visiting them a better experience for everyone.