This review covers:
• The division of labor between HTML and CSS
• Introduction to HTML:
    • Parents, children, attributes
    • Indentation
    • Semantic elements
    • Paragraphs, links, images, lists
• Introduction to CSS:
    • Where can we write it and what difference does that make?
    • Selectors (id, class, element type), properties
    • How to structure a CSS file
    • Naming things
• External files: relative and absolute paths
• Getting to know your text editor