Chapter 12

Coding and Debugging Your First Web Application


Reviewing code to see pre-existing functionality

Writing code by following steps to create your app

Debugging your code by looking for common syntax errors

Talk is cheap. Show me the code.


It may not feel like it, but you’ve already done the majority of work toward creating your first web application. You painfully broke down your app into steps, and researched each step to determine functionality and design. As Linus Torvalds, creator of the Linux operator system, said, “Talk is cheap.” So let’s start actually coding.

Getting Ready to Code

Before you start coding, do a few housekeeping items. First, ensure that you are doing all of the following:

  • Using the Chome browser: Download and install the latest version of Chome, as it offers the most support for the latest HTML standards, and is available for download at
  • Working on a desktop or laptop computer: Although it is possible to code on a mobile device, it can be more difficult and all layouts may not appear properly.
  • Remembering to indent your code to make it easier to read: One main source of mistakes is forgetting to close a tag or curly brace, and indenting your code will make spotting these errors easier.
  • Remembering to enable location services on your browser and computer: To enable location services within Chrome, click on the settings icon (3 horizontal lines on the top right of the browser), ...

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