Enable Archive log mode in Oracle DB

How to enable archive log mode in oracle 10g or 11g
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This is how to enable archiving:

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Productio
With the Partitioning, OLAP and Data Mining options

SQL> archive log list
Database log mode No Archive Mode
Automatic archival Disabled
Archive destination USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence 26
Current log sequence 28

SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.

SQL> startup mount
ORACLE instance started.

Total System Global Area 289406976 bytes
Fixed Size 1248576 bytes
Variable Size 96469696 bytes
Database Buffers 184549376 bytes
Redo Buffers 7139328 bytes
Database mounted.
SQL> alter database archivelog;                           For no archive log mode: sql>alter database noarchivelog;

Database altered.                                                                 Database altered.

SQL> alter database open;                                                         sql> alter database open;

Database altered.                                                                 Database altered