Difference between Ad Free Credits and Ad Free Impressions

1) What is the difference between Ad Free Credits and Ad Free Impressions?


2) If I use a One Time Ad Free Credit Option such as 25,000 Ad Free Impressions for $7.00, will it remove those annoying banners on the top of my forum's page for 25,000 visits?

Ad free credits and impressions are the same thing Both are based on pageviews.

If you have an unlimited ad free plan then pageviews do not matter.