PALO language Home Page
.UNED University

PALO is a proposal of Educative Modelling Language  to describe and design learning content and learning environments  at a high level of abstraction using learning content ontologies and conceptual maps to search and retrieve small-granularity Learning Objects.

PALO is based on a  reference framework  to design educative content based in  levels of abstraction. Each level identifies a certain  group of related components or elements of a learning resource.  The language  allows to define teaching strategies  by mean of   the definition of specific DTD's called instructional templates This templates are a general type of PALO document that specially suits for a given instructional or teaching purpose.

PALO has been designed to be a  technology-independent representation of a learning reseource, thus allowing educative content interchange , interoperability, mantainability and reusability. A PALO description of a learning content (a *.palo file) can be turned into a variety of  learning scenarios (each one built using an specific  delivery format) via a compiling process. 

Educative content  written in PALO has been tested since academic yesr 99/00 at the SENSEI educative web site of the Dept. of Languages and Computer Systems of UNED University. During current year, 2003/2004  open courses written in PALO are on use in SENSEI website.


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Examples &
PALO has been in use sice 1998. Actually, more than 700 students access to a variety of Courses developed and written in PALO Language.


  • Some PALO definition and their corresponding learning environment s can be browsed  at the DIVILAB web page.
  • See the DEMO page with real applications of PALO Language at UNED University.
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Links &
Some publications related to PALO language:
  • Ph. D. Thesis (In Spanish!) [HTML]  "Una Arquitectura Cognitiva para el Diseño de Entornos Telemáticos de Ensñanza y Aprendizaje" Director: M. Felisa Verdejo Sep 2000
Conference Papers
Technical Reports:
PALO Language Overview (Jan 2002) [Draft version]
CEN/ISSS Survey on Educational Modelling Languages (Sept 2002)


  • CEN/ISSS 9th Meeting in Torino (2001) --- Track on Educational ML's
  • A view of  Learning Content (1 slide, 2003):   PPT
  • Authoring Learning Content: Why Learning Objects and why Modelling Languages (2004): PPT
Activities and uses of Educative Modelling Languages  Links to other proposals of  Educative Modelling Languages
  • EML (Educational Modelling Language) - Open Univ. Nederland (See Also IMS-LD)
  • TML (Tutorial Markup Language)
  • UML (Universal Learning Format)
  • Targeteam
  • PML (Procedural Mark-up Language)
  • LMML (Learning Material Markup Language) -University of Passau
  • TeachML -University of the Army Forces, Germany
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Tutorials Basically a PALO compiler is a software tool that turns this file  into this environment.
A PALO overview can be found in the Technical Report mentioned above.
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Tools & 

PALO files are processed using a PALO Compiler called paloc. This tool was developed in PERL and based in the SGML parser developed by Earl Hood. The compiler is invoked and configured from an visual interface developed in Tk/Tcl. Software is available for academic and archeological purposes but take seriously  into account that: 1st) It is NOT a formal distribution and it is not supported, 2nd) It is a complete mess!! No one has reported so far to get it installed. Please don't ask how! 

We are currently working on a freely available version of PALO compiler in Java.  PALO compiler will have GPL copyright policy. Volunteers can join with an email to miguel.rodriguez AT

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PALO Language has been developed thanks to the support of the Spanish Ministery of Science and Technology and the CICYT comission in the framework of the STEED Project.

PALO is not an acronym. The name of the language is inspired by the name of the the small city of  El Palo,  located at the east of Malaga, in Spain. 


Miguel R. Artacho  LTCS Group