What is web development? (Beginner)

Web development is a broad term for the process of writing a web page or site. Web pages are written with HTML, CSS and JavaScript. These pages can be simple text and graphics that resemble a document. Pages can also be interactive or display changing information. Interactive server pages are a little more complex to write, but they enable richer web sites. Today, most pages are interactive and provide modern online services like shopping carts, dynamic visualizations, and even complex social networks.

Source: MSDN