In line editors for different document types help make the alfresco web client more useful. Alfresco ships with a inline HTML editor. What it means to be 'inline' is as follows. You can edit the document directly within (or in line with) the alfresco web client.
Another example of an inline editor is and XML editor which presents the user with a UI, hiding the complexity and technical aspects of XML.
About the Example
This guide is a tutorial for adding editors to the web client. As an example we will add the editLiveForXml editor to the Alfresco webclient.
This tutorial is in no way connected with Ephox or is it suggesting that you should or should not use the Ephox EditLive for XML product. The editor is available for download, largely comprehensive, and thus is suitable as an example.