Introduction to PAELLOS

PAELLOS is a French acronym meaning Plateforme d'Apprentissage En Ligne Libre Orientée Sémantique (Free online sematic-oriented platform). PAELLOS includes :

• A system to edit courses and exercises (WebJaxe) allowing many authors to work together online on a project.
• A server providing a web interface for distance learning students and tutors based on these courses, and an administration interface.

PAELLOS is libre software (free as in speech) as well as free (as in beer) : the source code is provided with the software, and it is possible to change it and redistribute it so long as the source code is redistributed with the changes.

If the previous characteristics are not unusual, PAELLOS has the particularity to be semantic oriented. The editor used to create courses is indeed graphical, but not WYSIWYG : the focus is on the meaning of the different parts of the text by opposition to the way they will look on the web site. Authors edit XML documents (without having to know the XML syntax), and several websites can be automatically generated from these documents based on the documents semantic structuring. With the presentation well separated from the content, it is easy to change the appearance of the websites without touching the contents.

PAELLOS was designed and created specifically for online trainings in astronomy. It is thus adapted to fully online trainings, while other learning platforms are more oriented towards on-site learning with additional online course material. A highlight for all trainings in sciences is the integration of an equation editor in the content editor and in the reply editor used by students to write replies to exercises. The implementation took into account the needs expressed by students, tutors and administrators over many years, while still remaining lightweight. The interface is simple and functional.