Tag attribute @id@ plays a crucial role in web development as it allows JavaScript to identify a DOM element. That's why class @Component@ provides two dedicated methods to set this attribute. With method @setOutputMarkupId(boolean output)@ we can decide if the @id@ attribute will be rendered or not in the final markup (by default is not rendered). The value of this attribute will be automatically generated by Wicket and it will be unique for the entire page. If we need to specify this value by hand, we can use method @setMarkupId(String id)@. The value of the id can be retrieved with method @getMarkupId()@.