XML's basic unit of data and markup is called element.
The element NAME mostly describes the kind of data/text that is contained within the element.
Example of an element:
<paragraph>This is a paragraph</paragraph>
Another example of an element:
<name>Keun-Hae Youk</name>
XML itself imposes no restrictions (except some restrictions on characters that can be used) on the element name. The language author decides what name is appropriate for the particular data/structure.
In so called document-centric XML, the element names mostly describe the structural and/or semantic role of the enclosed text, in its context.
Add element names to each line in your text document. Use an appropriate semantic to describe the element content.
Note that XML element names can not contain spaces.