Documents are a simple, yet effective area of the system that allows you to build up a bigger and more detailed picture of your client. This area of the system allows you to load in any document that you have on a customer and not only store it online where it will be accessible from any online device but you can store it against the customers record.
These documents could be simple things like offline sales quotes that you link up to a contact for future reference or even scans of hand written notes stored within the system rather than the original scrap of paper.
Documents that are uploaded to the system can also be used within email campaigns, rather than sending attachments to bulk records, you can link a document and track who is downloading/opening it!
Here are other relevant documents:
Linking Documents to Email Campaigns