Within each unit a similar structure as on lesson level is employed. However, the elements glossary, bibliography and metadata are always defined for the whole lesson on lesson level. The actual content within a unit is stored in a number of so-called "learning objects" (not to be confused with the learning objectives – called "goals" within eLML). Each learning object describes a certain concept, model, equation, term, or process using all or some of the three elements clarify (theory), look (example) and act in free order. These three elements can have a special visual representation when transformed into a presentation format – e.g. a "gear" icon for act elements as used in GITTA to signalize the student that he or she has to "do" something – but their main purpose is to guide authors while creating content. Using the elements clarify, look and act, the author has to think about how a certain concept can be presented best to the student. Whether a learning object starts with some theory (clarify element) and continues with one or more examples (look elements) or, alternatively, the student first does something (act element) and then read the theory afterwards (clarify element) is left to the author.