If you're like me and you haven't played with S3 and are wondering what an object is, here's a relevant excerpt from the Wikipedia entry on S3 to add some context:
"S3 stores arbitrary objects (computer files) up to 5 terabytes in size, each accompanied by up to 2 kilobytes of metadata. Objects are organized into buckets (each owned by an Amazon Web Services or AWS account), and identified within each bucket by a unique, user-assigned key. Amazon Machine Images (AMIs) which are modified in the Elastic Compute Cloud (EC2) can be exported to S3 as bundles."