What is a responsive website?
Then and now
Before mobile devices existed, a website was built to work well on the most common (desktop) screens. With the arrival of mobile phones and tablets with internet, it was important to keep the website readable on these small screens and to ensure that visitors did not have to scroll from left to right.
In the beginning, some of the larger companies made separate websites for mobile use. The website detected the screen format and presented the user with a special site, usually with limited options.
A responsive website automatically adapts to the screen size. Some elements such as photographs become smaller and other layout elements change their behavior. Think of a dropdown menu instead of a text menu with separate buttons. The margins (white spaces) often also change in order to save space on the screen.