A web designer works on the visual aspect of the website, such as the aesthetic portion. They use different types of programs to effectively create the visual element of the website.
The web developer completes the process and make a functioning website from it. Web developers use PHP and other programming languages to bring life to the design files.
So, each member has a specific role based on the type of technology, tool or programming languages. Thus, the designer and developer are essential to effectively create a functional website