Conventions used

There are a number of text conventions used throughout this book.

Code in text: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "If we look at the source code for this component in App.js, we'll see that there's already a CSS header element in the return function."

A block of code is set as follows:

.App-logo {
  height: 40vmin;
  pointer-events: none;
}

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

  import './Header.css';
- function Header() {
+ function Header({ logo }) {
    return (
      <header className='App-header'>

Any command-line input or output is written as follows:

npx create-react-app chapter-2

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: "Select System info from the Administration panel."

Tips or important notes

Appear like this.