Introduction to CSS Selectors


Selectors are the heart of CSS.

They tell the browser exactly which HTML elements should be styled.

Why Selectors Are Important

Without selectors, CSS would not know where to apply styles.

Selectors make styling precise and powerful.

What a Selector Does

A selector chooses one or more HTML elements and applies styles to them.

This selector styles all paragraph elements on the page.

Types of CSS Selectors

In this chapter, you will learn:

  • Element selectors
  • Class selectors
  • ID selectors
  • Grouping selectors
  • Descendant and child selectors

How Selectors Work in the Browser

The browser:

  1. Reads the HTML.
  2. Finds matching selectors.
  3. Applies styles to those elements.

Why Learning Selectors Matters for Jobs

Every frontend developer uses selectors daily.

Strong selector skills make your CSS efficient and professional.

Common Beginner Confusion

Many beginners think CSS styles everything automatically.

In reality, only elements matched by selectors get styled.

Think Like a Professional

Professional developers:

  1. Use clear selectors
  2. Avoid unnecessary complexity
  3. Keep styles easy to maintain

Practice Task

Look at any HTML page and ask:

  1. Which elements do I want to style first?

What You Will Learn Next

In the next lesson, you will learn how to use element selectors.