It supports many languages. There are many themes for syntax coloring. It has many useful features which are detailed here:
Here is a brief tutorial how I used it in our JSP page:
1- Download and extract latest stable version from here:
2- There is only one directory to embed to your project. I used(you may prefer one of other optional folders) “src-noconflict” directory and named it as “ACE” and loaded it to root path in our web project to use from “/ACE” URL path.
3- Add following meta to the top of head section of your existing page:
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
4- Add editor component to wherever you want to embed in your page:
<form method="post" ... onSubmit="var editor = ace.edit('JavaEditor');document.frmInput.SourceCode.value=editor.getValue();">