What does grouping in Access mean?

Answer 1

In a query, it is creating groups of records that share some common characteristic, in order to do things with them. For example, if you wanted to get the total amount of employees in each department in a company, you would count all employees, grouped by department. That would give a total for each department. You could find the highest wage in each department. You group by fields that will have common values, like employees having departments in common. Others you might group by would be gender or class or marital status. You would not group on things that are likely to be different for everyone, like phone number or date of birth.