v$log and v$logfiles

v$log has one row for each group.

v$logfile has one row for each file.

There is a status column for v$log. 

Current means the group is being used.

Inactive means the group is not in use and will not be need for instance recovery if the instance crash now.

Active means the group is not in use but will be used for instance recovery if the instance crash at this moment