An impression, in online advertising, is an appearance of an ad on a web page. Internet advertising costs are often measured in cost per impression [1] or CPM [2].
An impression, in online advertising, is an appearance of an ad on a web page. Internet advertising costs are often measured in cost per impression [1] or CPM [2].
Links:
[1] http://www.wordstream.com/cost-per-impression
[2] http://www.wordstream.com/cpm