Data convey information about multiple observations or things being examined. Even more foundational to our goals in statistics, data are characterized by variation or differences between observations. 

We frequently convey data in a table.

We frequently convey data in an Excel table, as displayed on the left. 

Unit of Analysis: The unit of analysis distinguishes each observation or row. Each unit represents an individual in this case, so each row is its unique observation uniquely identified by a first name (e.g., Emily or David).   

Variable: A variable represents a characteristic of interest for your observations. Each variable is characterized by its own column (e.g., gender or salary)

Value: Each observation has a value that represents the observed characteristic for the associated variable. For example, the table shows that Jessica is a woman whose salary is $55,000.