Including CSS styles inline in an HTML document can be helpful in certain situations, such as when you want to apply a unique style to a single element on a page. You can use the `style` attribute on the relevant HTML element to include CSS styles inline.

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**Advantages:**
- They allow you to apply unique styles to individual elements, as shown in the example above;
- This can make your HTML markup cleaner and easier to read and can make it easier to maintain and update your styles.

**Disadvantages**
- It can make your HTML markup more cluttered and difficult to read since the styles are included directly in the HTML elements rather than in a separate stylesheet;
- Using inline styles can make it harder to reuse styles across multiple elements or pages;

CSS, or Cascading Style Sheets, is a stylesheet language used to describe the presentation of a document written in a markup language like HTML. CSS is a fundamental building block of the modern web and controls the styling and layout of websites and web applications.

This section will cover the basics of CSS. You will learn the language's syntax, the most common CSS properties, and how to add CSS styles to your web page.

Selecting the elements you need becomes more challenging as your HTML code's complexity grows. This section will cover more advanced techniques of the selection.

This section will cover the general styling used for layout and text formatting to create a visually appealing and user-friendly design for your webpage. Part I.

Introduction to CSS Part I

Including CSS: Inline Styles