What are Campaigns?
Campaigns are a concentrated effort to align all channels around a single offer and goal. The campaign overview page provides a summary of how the campaign is performing by rolling up the metrics from individual pieces of content into aggregate metrics. This video provides a quick overview of the uses of this tool.
How to analyze a campaign - http://knowledge.hubspot.com/campaigns-user-guide/how-to-analyze-a-campaign-in-hubspot
Campaign training - http://academy.hubspot.com/campaigns-videos-training/