The name representing each bucket is the file name (which you specify on upload) or bucket_name. Multiple buckets can have the same name, but their bucket_key (automatically generated if not specified) is unique. The event count below each bucket displays the number of event data points contained in that bucket. The date displayed to the right is the date the most recent data point was added.
If the bucket was created through a file upload, then a "settings" link will appear below the bucket name. If the bucket was shared, then "Shared by ____" will appear below the bucket name.
A bucket must be selected from the shelf before it can be visualized in Waves, Lines or Tiles.
To hide the Bucket Shelf, click the gray icon directly to the right of the Shelf in the top toolbar. Clicking this icon again will reveal the Bucket Shelf.