A database snapshot is more about having a frozen, query only, copy of the database than it is about backup & recovery. However, in some circumstances it may be useful to retain a 'before' image of a database when making a Change (e.g. perhaps this would be quicker to recover and/or need less storage than a typical backup/restore approach).
CREATE DATABASE MyDatabase_snapshot ON
( NAME = MyDatabaseFileID,
FILENAME = 'E:\my\database\datafile\path\MyDatabaseSnapshotFileName.ss' )
AS SNAPSHOT OF MyDatabase;
GO
DROP DATABASE MyDatabase_snapshot;