If you need to embed script into a content editable page in SharePoint 2013/Online, you may decide to use the new Script Editor web part. There are often many preferable ways to add script to a page (e.g. via the master page, a custom action, custom control, the ScriptLink property, etc.) however this is an easy option for demo purposes or when deployment activities are out of scope.
<script> tag otherwise it will be rendered as text. However, if you fail to provide the required
CAVEAT: As I stated in the first paragraph, this is often not the best way to add script to a page.