This section contains a brief overview of how CloudSlang and the CloudSlang Orchestration Engine (Score) work. For more detailed information see the :ref:`Score API <score_api>` and :ref:`Slang API <slang_api>` sections.
The CloudSlang Orchestration Engine is an engine that runs workflows. Internally, the workflows are represented as :ref:`ExecutionPlans <execution_plan>`. An :ref:`ExecutionPlan <execution_plan>` is essentially a map of IDs and :ref:`ExecutionSteps <execution_step>`. Each :ref:`ExecutionStep <execution_step>` contains information for calling an action method and a navigation method.
When an :ref:`ExecutionPlan <execution_plan>` is
triggered it executes the first
:ref:`ExecutionStep's <execution_step>` action method and
navigation method. The navigation method returns the ID of the next
:ref:`ExecutionStep <execution_step>` to run. Execution
continues in this manner, successively calling the next
:ref:`ExecutionStep's <execution_step>` action and
navigation methods, until a navigation method returns null to
indicate the end of the flow.
CloudSlang plugs into the CloudSlang Orchestration Engine (Score) by compiling its workflow and operation files into Score :ref:`ExecutionPlans <execution_plan>` and then triggering them. Generally, when working with CloudSlang content, all interaction with Score goes through the :ref:`Slang API <slang_api>`, not the :ref:`Score API <score_api>`.