There are 2 types of data: dimensions that describes characteristics, sessions and actions of users, and metrics - quantitative measurement of data, that is presented in numbers. Both of them are essential to analyze. See the example of data types below.
The metric called Visitors or users.This metrics is used to measure the unique number of unique users who visit your site during the certain time period. This metric's used to understand the size of the audience.
Visits, known as sessions, are defined what pages your user visited. Google analytics count these actions, literary each page that has been viewed.
Bounce range - key metric. the persentage of session with only one users interaction.
