This xml is used to set the string values for application use, then other place can use the value by using @string/Tag name
for example:
In strings.xml:
In main.xml:
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/main_search_term"
android:completionThreshold="1"
android:selectAllOnFocus="true" />