I ran the UTLBSTAT and selected the view v$rowcache. now, can someone please tell me what do these data represent? Thank you!!

SVRMGR> SELECT parameter, gets, getmisses
2> FROM v$rowcache;
PARAMETER GETS GETMISSES
-------------------------------- ---------- ----------
dc_free_extents 147 32
dc_used_extents 23 23
dc_segments 117 45
dc_tablespaces 106 3
dc_tablespace_quotas 0 0
dc_files 0 0
dc_users 76 8
dc_rollback_segments 126 4
dc_objects 558 109
dc_global_oids 0 0
dc_constraints 4 3
dc_object_ids 302 50
dc_synonyms 7 4
dc_sequences 3 2
dc_usernames 64 5
dc_database_links 0 0
dc_histogram_defs 8 4
...

I tried to make it easier to read, but it doesn't come out the way I wanted. Please bear with me. Tks.