Front-End Web Development

What it covers

Front-end web development is the work of building the part of an application a person touches: the document, its styling, its behaviour, and the pipeline that delivers it. It spans the platform languages, the framework you compose them with, and the two qualities that decide whether the result is usable — accessibility and speed. The field is usually described by its tools, which change, rather than by these layers, which do not.

Why it matters

It is the layer where every product decision becomes visible, and the layer with the widest audience of interpreters: a browser rendering for one person, a screen reader describing it to another, a crawler indexing it for a third. Getting the markup and the delivery right serves all of them at once, which is why the fundamentals here outlast every framework.

Included skills

• Cascading Style Sheets (CSS) (02-frontend/05-css) — the cascade, the box model and the layout systems.
• Javascript (02-frontend/06-javascript) — the language that makes the page respond.
• React (02-frontend/29-react) — one mainstream way to compose an application from components.
• Accessibility (WCAG / a11y) (02-frontend/11-accessibility-wcag-a11y) — making the result usable by keyboard and assistive technology.
• Web Performance (Core Web Vitals) (02-frontend/26-web-performance-core-web-vitals) — the measured experience as the page loads and responds.

Where to start

Start with CSS and JavaScript together: they are the two layers everything else sits on. Add React once the language and the document model are familiar, because a framework is most useful when it is not also teaching you the platform. Accessibility belongs alongside the markup decisions, not after them. Web Performance comes last, when there is a real page to measure.