Use custom properties to supply your own name/value pairs of business component metadata which the framework can access at runtime. Properties are often user-supplied data that provide hints, UI formatting clues, notes to users, etc. You can set custom properties on Entity Objects, View Objects, Domains, and Application Modules, as well as the individual attributes of an Entity or a View Object.
The fundamental benefits of using properties are the following:
You can set a property to any string value.
Overriding Property Values
Getting and Setting Properties at Runtime
Using Properties to Dynamically Generate the UI