There are five major types of reports:
- Logs - A simple list of datapoints and their associated data. (Examples)
- Result - A simple list of group members and their associated aggregate data. (Examples)
- Crosstab - A structured breakout of one group vs one or more other groups. (Examples)
- Nested - A hierarchical breakout of groups and the groups within them. (Examples)
- Entire Datatype Aggregate - Numbers calculated across the entire datatype, without being broken out by group. (Examples)
A video explaining these report types in more depth can be viewed here.