Aspects are one of the ways to model content. Are you familiar with Object Orientated modeling using Java? Aspects are a bit like interfaces, types are like classes.
Let me try again, in case I lost you above… And apologies if I stuff up on the specifics of the Maritime Transportation industry.
Alfresco allows you to model different content types, so you can have represent what is important for your business.
For example you could have a content type to represent a "shipping document" or a "weather forecast". For the sake of our example lets say that a shipping document only makes sense if it has two properties called "from" and "to". We could also specialize the shipping types to have "shipping document by road" with extra details about the truck or "shipping document by sea" with details about the captain, the boat's name, etc, etc.
While that approach will take you so far there are some things that are not directly associated with the type. For example imagine that there is an optional bonus for on time delivery. Or some special procedures for transporting hazardous materials. While we could model this as "shipping document by road with bonus and hazardous materials" and all the combinations thereof, that may become unweildy. So instead we could create a "hazardous" aspect and a "bonus" aspect which can be applied to all types of shipping document. We could also apply the aspect to some other type of document, say a "warehousing document".
While this all sounds esoteric and is perhaps a little contrived when you come to thinking about how to represent content in Alfresco and what forms are required then it may become clearer. To some extent object modeling is an Art form rather than a Science, however you will know when you have a solution that is good enough. And in general aspects are a good thing that you will want to use.
