The Description and Title annotations recommend values for a Smart Client to use to describe data within its user interface.
The Description annotation provides a recommended (or friendly) value to describe an entity, property, etc.
The Title annotation denotes the property used to represent instances of complex or entity types and typically points to the Name (or similar) property for an entity.
For example, review the annotations metadata document for the SampleService:
https://sam.spclouddave.com/SampleService/Sppid/v2/Annotations/$metadata
If you look at the Equipment entity, you will see the following metadata annotations for Description and Title:
<Annotations Target="Com.Ingr.Sppid.V1.Equipment">
<Annotation Term="Org.OData.Core.V1.Description" String="A base type for all equipment entities"/>
<Annotation Term="Org.OData.Core.V1.Description" Qualifier="ru-RU" String="Базовый тип для всех объектов оборудования"/>
.
<Annotation Term="Com.Ingr.Core.V1.Title" PropertyPath="Name"/>
</Annotations>
If your Smart Client contains a grid populated with rows of equipment, you would use the Equipment/Name property for the first column.