Web developers are broken down into 3 categories. Front-end, back-end and full stack are the three types of developers that exist in the field of coding.
Front end Web Development

Front end web development is the interface or the client side . This is typically JavaScript or CSS. Most of this work would be implementing the visual elements that clients or customers interact with. I have even heard some of my peers talk about using AI to help them start or get an idea of website or template they would try and use.
Back end Web Development
Back end web development is pretty much just writing the code that communicates between the data bases and the server. Data structures, MySQL and algorithms are all key components of back end web development. This is also a place where data storage and security for the website can be found. If the company website receives payment on their website, you will need to code a way for their to be a payment method available.
Full stack Web Development
Full stack developers are exactly what they sound like, these special people are gifted enough to complete both front and back end web development well. People that poses this ability will be sought after by most if not all tech companies and will make anywhere from $77k-$129k according to Glassdoor. Full stack web developers are often able to put their business ideas into practice with their ability to create any kind of website or application that they desire.