That page is equal to six hits, the page and then the five graphics. This is wrong, as it creates an inflated report of site traffic. If I could report hits alone, I could create graphics-filled pages and report numbers into the tens of millions. It may be that one person saw the ad banner three times. That' s fine.
Impressions are simply the number of times the banner was seen.
Usually this number is reported right alongside Impressions. Something like, HTML Goodies creates 3 million impressions a month from 1.1 million individual visitors. When I first started Goodies, I made a point of making my pages one hit each, three at the most. The reason was that I sold by impressions, but I payed by hits. I wanted the two numbers as equal as possible.