XML Tags are the foundation of XML because they define the scope of an element in XML.
Furtheremore, they can also be used to insert comments, declare settings needed for environment analysis, and to insert special instructions.
We can classify XML tags as follows:
Every non-empty XML element starts with a start-tag.
Every element that has a start tag should end with an end tag.
The end tag includes a
/ before the name of the element!
The text that appears between start-tag and end-tag is called content.
An element which has no content is called empty.
An empty element can be represented in two ways:
A start-tag immediately followed by an end-tag
or, a complete empty-element tag
Empty-element tags (showed in the second example) can be used for any element which has no content.
XML Tags Rules
Each XML tag must adhere to the following rules:
Rule 1: XML tags are case-sensitive
A wrong example:
<Name> are two different tags!
A correct example:
Rule 2: XML Tags order must be respected
An XML tag opened inside another element must be closed before the outer element is closed
This tag is closed before the outer_element