GUESTUnknown Person:I have to assume you're not in the US; anyone here, I think, would recognize the term "junk mail". The Postal Service dislikes the term intensely, which I suppose is no surprise.
It means advertising circulars and the like, almost always unsolicited, addressed in huge numbers to names on large-scale mailing lists, or to "occupant" or the like. The Postal Service delivers this stuff at preferential low rates (no kidding), and the poor first-class mail user has to pay higher rates as a result.
Thank you for what I take to be a compliment.
Dave Oesterreich