Difference between Searches and Impressions

[flyntime_tx]

I've been using the Bing Ad Intelligence tool (which is great!), but I'm confused about one of the metrics and even the Microsoft customer support guy wasn't too clear.

I search on "wills and trusts" and I get results that say there are 2,347 searches, and 7,228 impressions.   How can there be more (ad) impressions than there were searches?  If it was 5 searches and 1 impression, I'd assume that meant an ad didn't appear for all the searches.  Makes sense.  But 1 search and 2 impressions ... how does that happen?

Appreciate any help, probably a dumb question but has me puzzled.  Also, I hope non-Moz tool questions are appropriate.

Thanks!

[LinkWheelOldSchool]

I think it has something to do with keyword match types (it's the same thing as with google adwords) - http://advertise.bingads.microsoft.com/en-us/help-topic/how-to/50822/what-are-keyword-match-types-and-how-do-i-use-them

[MattAntonino]

I don't do a ton of Bing ad work so this may be incorrect but the way I understand it is that you're selling the total number of ads that appeared (impressions.)

So if one search for wills returns 4 ads on the side, that's 1 search, 4 impressions.

Yours shows about 1 search per 3.1 impressions. That sounds like my understanding of this would be correct but again, this is my understanding. I'm not 100% sure.