A timestamp is generally a Databse vocabullary wich means a date format, the real stored dateformat that you'll certianlly not remark else you've already read about it, in the database, the date and time and stored together in the fomrat [Date] : [Time] >> mm/dd/yyyy: hh:mm:ss, so where you intend to inset a date row, the data will be in this : 10/05/2003 00:00:00 and when dealing with time only you get this 12/31/9999 10:30:32 it's a technique that makes the storing effort more easy for the DBMS (Data Base Managamement System). That's why it's always advised to try to make use of that's feature, not just for the data itself but maybe for other purposes for example when inserting the date of an operation such as sale, stock entry, it would be very usesfull to inset the time within when that date row cost time and date, so why passing through !
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veryuseful..Really
It's true for interbase too !