The Code Editor
The code editor is where you can do your code writing. It is designed a fully-featured editor, similar to what other apps provide.
In this editor you have:
Each single line has its own number.
Different parts of the code are written in different colors, depending on the type they represent.
Code Block highlighting
Blocks of code can be highlighted by clicking on the beginning or ending tag. The corresponding tag will be highlighted.
Each block of code can be collapsed or expanded
A Preview area
(the web viewer on the right)
Advanced Search capabilities
At the top right is a search box. Here you can search inside the editor. You can also replace.
This simply saves the code so that it will be rendered to the preview area. Command (Control) + S will also save.
As you type the opening tag of an element, this code editor will auto-type the closing editor. This is also true for single or double quotes, bracket or curly brace pairs.