Hi
A hot backup is when you take a backup when the SQL Server is still runing.
For example with the command BACKUP DATABASE (
BOL Description)
A cold backup is when you stop the SQL Server, and the database is no longer avalibale to the users, and then you backup the MDF, and the LDF files with som backup software.
Regards
Jens Nilsson
MCTS - SQL Server 2008 Imp. and Main.