Defines root-object of lml. Other objects like table, information or charts are child-tags of this object. Defines global constraints, keys and keyrefs. Defines which main tags are allowed in LML. This attribute defines, if this lml-file mainly contains layout-information. If layout-value is true, then only layout-tags are checked. Therefore graphical objects do not have to be valid against XSL-checks in a layout-lml-file. Root-tag of LML-scheme. Abstract type for all graphical objects. All graphical objects like table, usagebar etc. have to have ids. This is defined by extending all graphical objects from this type.