The target attribute specifies a pointer to another element in the tbx markup. The link is established when the value of the target attribute of the source element is the same as the value of the xml:id attribute of the target element. When this attribute is used with terms, such as <tbx:entailedTerm> or <tbx:crossReference>, the target is often another term in the glossary section. The pointer is a unique identifier. The content of elements that take this attribute is typically the display value of the target element, such as the target term. The elements that take this attribute cannot be empty; display content is mandatory.