The following image describes service management domain model and the relationships between objects.
An ops change request is a request for change that has been submitted to the IT operations group, in response to particular problems or incidents. A change request can affect any number of configuration items (CIs). The CIs may include web pages, images, source code files, etc.
A problem is a description of an issue that needs resolution. This may be a defective software issue, a hardware failure, or any other type of problem. Problems have a unique workflow. A problem may be related to any number of incidents and change requests.
An incident is a specific occurrence or symptom related to a problem. For example, while a problem might describe a known software issue that needs to be resolve, an incident describes specifically what happened to a particular user and may provide steps to work around in. Incidents follow their own workflow. They may be related to any number of problems, change requests, or knowledge-base articles.
A CI may be any object that is affected by a related change request. CIs are classified into types, categories, and subcategories. A simple example is a server. A server is a hardware node, and the service to be implemented may be carried out on it. Another example is an application. An application is simply a collection of software objects, residing on a server, that may be affected by the originating service request. Configuration items may be related to any number of other configuration items.
A knowledge base (KB) article is a document stored in a knowledge base that describes symptoms of a technical issue, and provides instructions for working around the issue.