Towards a taxonomy of errors in HTML and CSS.

As part of a larger research agenda to explore web development as a context for learning computational literacy skills, we investigate errors people make while writing code in HTML and CSS. We report on a lab-based study in which 20 participants were video recorded as they completed coding tasks. We have applied the skills-rules-knowledge framework to segment this data by the cognitive causes of errors they made, and present a taxonomy of these errors. Our findings demonstrate how the skills-rules-framework can be used to analyze coding errors, provide insight about the origins of these errors, and suggest ways that the design of web development tools can be improved to support learning and practice with HTML and CSS.