IMS Learning Design (from now on referred as IMS-LD) is a specification done by the IMS Global Learning Consortium. It is an XML-based description for e-learning. It provides a global framework for including the description of different pedagogical and methodological learning models. Therefore IMS-LD is independent from a concrete pedagogy or methodology. The XML file that is compliant with IMS-LD specifies a set of learning activities (which are usually related to a set of resources and services) and who and when can do these activities and with which conditions. Therefore, it establishes a sequencing of activities for each role. IMS-LD is in principle independent from IMS Content Packaging (IMS CP), so it can be used without IMS CP. Nevertheless, the most common case is to insert the IMS-LD file inside the organizations element of an IMS CP and the result is called "unit of learning". A unit of learning, as defined in the IMS-LD specification, is an abstract term used to refer to any delimited piece of education or training, such as a course, a module, a lesson, etc. In this specification, the terms unit of learning and course are used to represent the same thing: a collection of ordered activities which has associated resources and services to learn that are going to be delivered to different defined roles and the workflow of the activities. Unit of learning and IMS Learning Design are not the same thing. A learning design is a description of a learning method used to achieve certain goals (learning objectives), and a unit of learning is the result of packaging a learning design (for example using IMS CP). There are some other terms introduced by IMS-LD that need to be defined, which are briefly explained bellow: Prerequisites. The previous requirements for learners for doing the unit of learning. Objectives: They are the goals to obtain in a unit of learning. Also it is possible to write objectives for each particular activity. Components. It defines statically the following elements of a unit of learning: roles, activities, environments and properties Roles. It defines the different types of users in a unit of learning. There are two basic types of roles: Learner and Staff. But additional roles can be defined. The roles form a hierarchical graph where the root roles are the basic ones. For example inside Learner role we can have additional roles depending on the students level or inside the staff role we can have professors, teaching assisstants, tutors, etc. .LRN. in fact, has defined predefined roles, so the sutdent role will be linked to the Learner one and the proffessor, teaching assisstant, etc. can be mapped to the IMS-LD corresponding ones. When there is no an exact correspondence, then we will create new .LRN subgroups that match with the IMS-LD roles. Properties. This is something that defines a concrete feature. There are local properties , local-person properties, local-role properties, global-personal properties and global properties. They are used depending on the scope of the property. Activities. An activity is something to be done, that usually has a description and an enviroment. There are two types of activities: learning activities (activities that are done by students in order to learn) and support activities (activities to support or help students, usually done by professors). Also there are structure activities which are an union of several activities that can be presented to the student either in a sequencial mode or for the user to select. The activities are the core of the workflow of the learning design. Environment. Collection of learning objects (for example files to be viewed by the student), services (like foros, chat, etc.) and sub-environments, in wich activities take place. When a student has to complete an activity that have a concrete enviroment, then he/she can do whichever of the learning objects and services that are defined inside this enviroment Service. For instance, a discussion forum, email, conference service and monitor service (to look at the properties). Method. It defines the dinamic part of learning design. It consists of several plays and contitions. If a method has several plays then each play is executed in parallel for all the roles. Therefore, for example a Learner can select in an instant of time between the different parallel activities (one activity for each play) Play A play has a set of acts. Each act is not executed until the previous one has been executed. Therefore, it can be viewed as a sequence of acts. A play finishes when all its acts has finished Act It defines what activity to do for each of role. Each role make the activity in parallel respect to the rest of roles. An act is finished when all the roles have finished its activity. This provides a synchronization point. Conditions. They are used in conjunction with properties to further refinement and to add personalization facilities in the learning design. By these way, for example is possible to take decissions taken into account the user profile, assessments done by the student, selections of the students during the course, etc. Notification. Allows to send messages between roles or to assign new learning or support activities to roles based on certain events. When integrating IMS-LD with .LRN, we take advantage of this capability in order to send messages between the system's components. This can only be done if .LRN is fully aware of the learner status inside the course. Item. When a component, a learning objective, or a prerequisite needs a resource, an item element is used. The learning design provides a semantic context for these items, so that runtime systems can know what to do with the resource.

There are tree levels of complaint in the IMS-LD specification: Learning Design Level A includes everything described above except the conditions, properties and notifications. It thus contains all the core vocabulary needed to support dedagogical diversity. Learning Design Level B adds Properties and Conditions to level A, which enable personalization and more elaborate sequencing and interactions based on learner porfolios. It can be used to direct the learning activities as well as record outcomes. Learning Design Level C adds Notification to level B, which, although a fairly small addition to the specification, adds significantly to the capability. There is a IMS Learning Design XML Binding document, where you can find detailed information about how each one of the elements described above is mapped in the final xml file.