[eZ publish] Why there are full, line, embed in the template?

Usually, the full view is used to view a content node with all of itsattributes. (We can think of a full content node view as a static HTMLpage of that element.)
The line view is used to view the content node in a list, for example,if we want to see all articles published in a given year.
The embed view is used if we want to attach a content node to another content node description attribute.