In a jART platform, two types of agents can co-exist:

• The NonRT-Agents are agents without temporal restrictions in their responsibilities.
• The RT-Agents are agents with at least one responsibility with temporal characteristics.

Each agent is formed by a set of behaviours. The behaviour concept is the abstraction that is selected to incorporate tasks to done in an agent. The behaviour concept is similar to the concept in Jade or the task concept in FIPA-OS. There are mainly two types of behaviours in jART:

• NonRT-Behaviours: without temporal characteristics.
• RT-Behaviours: with temporal characteristics.

Therefore, the RT-Behaviours can be classified into:

• Periodic-Behaviours: The task associated to the behaviour will be executed periodically.
• NonPeriodic-Behaviours: This behaviour allows the programmer to characterize a task that may become active at any time.

Depending on those definitions, there exist some important basic rules that must always be accomplished in the jART platform, these are:

• a) RT-Behaviours can only be employed in RT-Agents.
• b) NonRT-Agents can only include NonRT-Behaviours.
• c) RT-Agents can include RT-Behaviours and NonRT-Behaviours.