A friend who is learning HTML and CSS recently asked me about different careers in IT.
The U.S. Bureau of Labor Statistics Occupational Outlook Handbook has a good overview of IT job families.
Although the web industry is a subset of IT, practitioners are likely to find themselves exposed to adjacent domains of work. Examples include,
The web industry has a large IT component, but it is much more than that. People working in the web industry tend to have T-shaped skill sets. Here are some real-world examples.
A front-end developer might make use of both sysadmin and graphic design skills - both dedicated jobs in their own right.
This content strategist leverages her knowledge of HTML and CSS and occasionally ventures into the world of graphic design.
Many web practitioners are cross functional. Usually, large and well funded organizations can afford to hire specialists.
Chris Coyer has a good list of web industry job titles.
If you want to work in the web industry, you may want to consider non-IT careers, or careers involving overlap between IT and other job families.