How to find User Has what privileges and roles in Oracle Database

Simple way to find out "User Has what privileges and roles"

Query 

session_privs

session_roles

NOTE: above view only help to connected database user.

But All others user query

DBA_AQ_AGENT_PRIVS 

DBA_COL_PRIVS 

DBA_COL_PRIVS_MADE 

DBA_COL_PRIVS_RECD 

DBA_REPGROUP_PRIVILEGES 

DBA_ROLE_PRIVS 

DBA_RSRC_CONSUMER_GROUP_PRIVS 

DBA_RSRC_MANAGER_SYSTEM_PRIVS 

DBA_SYS_PRIVS 

DBA_TAB_PRIVS 

DBA_TAB_PRIVS_MADE 

DBA_TAB_PRIVS_RECD 

DBA_NETWORK_ACL_PRIVILEGES 

_DBA_STREAMS_PRIVILEGED_DBA 

DBA_WM_PRIVS 

DBA_WORKSPACE_PRIVS 

DBA_EXPFIL_PRIVILEGES 

DBA_RLMGR_PRIVILEGES

for the readymade scripts visit @ Scripts