Approval Workflow Status Values in MOSS 2007

The workflow approval status values are listed below:
the integer values:

0 - Not Started
1 - Failed on Start
2 - In Progress
3 - Error Occurred
4 - Stopped by User 
5 - Completed
6 - Failed on Start, Retrying
7 - Error Occurred, Retrying
8 - View Query Overflow
15 - Canceled
16 - Approved
17 - Rejected

Workflow in MOSS 2007

A workflow can be defined as a model to represent real work for further assessment, In computerized environment, workflow may mean a software solution to capture the events and actions of these assessments as an attempt to computerize the actual business process.

Workflows could be implemented in three different ways in SharePoint 2007. SharePoint 2007 has some OOB workflows. Simple workflows can be created using SharePoint Designer. More complex workflows can be developed in Visual Studio. SharePoint 2007 uses Windows Workflow Foundation (WWF) as an engine for workflows. WWF provides workflow runtime, and SharePoint lists and document libraries provide data repository for the items used by workflows.


If you are interested in knowing more this MSDN link is a good starting point: http://msdn.microsoft.com/en-us/library/cc514224.aspx#MOSS2007DevWorkflowSolutions_WorkflowPlatform