Properties

When you are working with the Office API objects you will need to use the object properties.
There are two different types of property: scalar and navigation.

Scalar Properties

These include primitive data types for example string, number and boolean.
These include arrays of primitive data types.
These include objects that are made up of primitive data types.
Scalar properties can be easily serialised.
These properties have to be loaded.

Examples include:

range.address - this returns a string "Sheet1!A1:B2" 
range.values - this returns an array of string/number/boolean ?? - returns an array of javascript objects (not Excel objects) 

Proxy Properties

Also known as Complex properties or navigation properties These include actual Office objects which are instances of classes that have methods.
These include collections of actual office objects.
These can be used to navigate across the Office object model.
These propeties always have a "load" method and a "context" property.
These properties do not have to be loaded.

Examples include:

range.format.fill - this returns an Excel fill object