To accurately answer this question we need to divide this concept into two main parts. Website development can be split into frontend and backend development. Both of these development fields require extensive knowledge about programming, operating system requirements, and online security. At the core of website development, the roles performed by a frontend and backend developer are outlined below.
Front-end developer is the person responsible for the visuals of the website. They are responsible for the websites' layout, design, and interactivity. Frontend developers achieve this by using HTML, CSS, and JavaScript programming languages.
Backend developer is the person who ensures that the website can collect and store data, ensures that the server that the website is hosted on is secure, and produces dynamic data to users of the website. Backend developers achieve this by using PHP, MySQL, Python, Ruby, and NodeJS programming languages.
In a nutshell, web development is the building and maintenance of websites; it's the work that happens behind the scenes to make a website look great, work fast and perform well.