The Simple Answer When analyzing site stats and traffic the one question that comes over and over is "What is the difference between a new or unique visitor? We'll keep it simple.
If I discover your site today and only visit once in the morning and once in the afternoon (from the same computer and same browser) I am one unique visitor. But I had two visits. The first time that I visited, I had a New Visit, because I had never visited before. The second time that I visited (that afternoon), I had a repeat visit (because I *had* visited before.) So in this example, we have two visits. We also had only one Absolute Unique Visitor and one New visit.