Rebuild Index:  
Throws away the complete index and rebuilds it from scratch.
This can be a long process but it is more complete then defrag/reorganize index.
Best used if the fragmentation is heavy (over 30%).

Can be done online in SQL2005 enterprise edition otherwise it means that the table is blocked
during the rebuilding.
Statistics are recalculated.

Defragment\Riorganize Index:
- Defrag/reorganize index : is faster then rebuild index but less complete.
You can use it when index fragmentation is under 30%.
Can be done online, meaning people can use the table when doing it.
Statistics are NOT recalculated

Sift Index Table
SIFT-tables are normal tables for SQL, so they will also be rebuild or defragged.
The 0-SIFT-records will NOT be deleted.
--> SSI utility delete 0 Sift table

SHEDULING
REINDEX FULL
Best use rebuild index once a week (e.g. Sunday)

DEFRAG
You can use defrag/reorganize during the night on weekdays or allfdays
--> If you use defrag, you also need to recalculate the statistics.
Of course the maintenance plans you make vary according to DB-size and time-windows
when you can do the actions.

STATISTICS
Recalculate statistics is best done every night (except in case of a rebuild index).

Sift Index Table
All nights

SEQUENCE SCHEDULING
SiftTable 0 delete
Defrag
Statistics
Reindex Full