Sessions is a metric in Google Analytics that represents a group of interactions made by a single user during a specified time period on a website or app.

Cost is the amount of money you have spent on your Google AdWords campaign. It can be viewed as a total cost or broken down by ad, keyword, or other customizable factors.

The Amount Spent metric in Facebook Ads represents the total cost of all clicks, impressions, and other ad interactions that generated charges for your campaign or ad set.

The Users metric in Google Analytics represents the number of unique individuals who have visited a website or app within a given time period. It is an important metric for measuring audience size and engagement.

Bounce rate is a metric that measures the percentage of visitors who leave a website after visiting only one page. A high bounce rate is often an indicator of poor website user experience or irrelevant content.

Clicks is a metric that measures the number of times users click on an ad and are directed to the advertiser's website or landing page. It helps advertisers gauge ad performance and user engagement.

Impressions is a metric in Google Adwords that refers to the number of times your ad has been displayed to potential customers on the Google search results page or on websites and apps that are part of the Google Display Network.

The Avg. Session Duration metric represents the average length of time users spend on a website, from the moment they arrive until they leave.

Pages per session is a Google Analytics metric that refers to the average number of pages viewed during a single session by a user on a website.

Avg. CPC stands for Average Cost Per Click, which is the average amount of money an advertiser pays each time a user clicks on one of their ads. It is a key metric in Google AdWords and helps advertisers evaluate the effectiveness of their ad campaigns.