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LON-CAPA is a web-based content management system that helps to organize and present your course website, deliver and manage assignments, and manage student enrollment, assessment, and grading. Typically all author functions will be completed using a web browser (Firefox, Chrome, Safari, IE or similar). The one exception to this is where your LON-CAPA domain has been configured to support webDAV access, in which case you may be able to carry out standard file operations (copy, move, add file etc.) using your computer's standard filesystem interface, after you have established access to your authoring space volume.

LON-CAPA has three work spaces: the ROLES menu, the course/community space where courses are developed from resources, and the authoring space where resources are composed and published. There are two user manuals for LON-CAPA, a course coordinator manual and author manual. Also, there are quick reference guides to building a course and building an exam, available at This is the author manual used to create resources such as problems that can later be added to your course.

Before creating problems, you should have:

Overview of the Authoring Process

Graphics, problems, and html pages are all considered resources. Additional resources include reusable snippets of perl, xml, cascading style sheets, etc. This manual documents the process used to create and organize the more advanced types of resources.

The authoring process involves these steps:

Importance of Planning your Directory Structure

Once a resource has been published, the published version can never be moved or deleted. Thus, it is important to plan your folder structure. Old resources can be marked obsolete, and the version in your authoring space deleted, but the published version(s) will remain in your folders in the locations in which they were originally published.

Understanding xml and the Colorful Editor

Problems are written in xml markup, which can appear complex when you first start to work with LON-CAPA if you have not done html or other coding. However, each xml element has a starting and closing argument, just like html. This manual includes a reference on xml markup used to write problems.

The authoring environment includes a 'colorful' web-based editor that can be used for authoring your first problems. Even experts will often start with the colorful editor to build a template for a problem. It is possible to switch back and forth between the colorful editor and xml when composing and testing your problems. Often simple issues are easier to clean up directly in xml. Also, it is easier to copy/paste xml to build additional problem sections compared to using the colorful editor.


The power of LON-CAPA for problem randomization and computing randomized answers is realized through writing perl script at the top of a problem. Example scripts are included in many example problems, and most resource authors publish scripts with the problems, so many examples are available. Many special functions have been created for use in scripts. This manual includes a section on writing scripts.

Maxima and R

Two computer algebra systems are interfaced to LON-CAPA, Maxima and R. This provides for algebra and calculus problems and responses. The R system has strong capabilities for statistics. Special script functions are provided to call Maxima and R to generate correct responses for a randomized problem, and also to check student responses.


Commenting your xml and scripts is important for both you and other users. Commenting within a loncapa/perl script is denoted with a #. This can be entered anwhere in a line and the remainder of the line will be ignored when parsing. Problems are coded in xml. Comments in xml are of the format <!- comment ->. However, it is important to know that the XML comments propagate through to the rendered web page viewed by students while the perl comments within the script are not. Hence, writing solution hints within XML comments is discouraged for obvious reasons.