Whenever we discuss quantities of data, we tend to do it in the abstract. We speak of a kilobyte, or a megabyte or a gigabyte without really knowing what it represents.
Based on content found at the website of James S. Huggins, this infographic enumerates the metric system names we use to measure data storage sizes. Also included are various common items that are measured in data terms- they are scattered throughout the graphic, placed relative to their average size. Perhaps this will help give some perspective to how big (or small) some of these terms we use are.