Code Example 1:

CREATE TABLE #T(
id INT IDENTITY,
dt DATETIME NOT NULL DEFAULT GETDATE(),
sdt SMALLDATETIME NOT NULL DEFAULT GETDATE())
GO

INSERT #T VALUES(DEFAULT,DEFAULT)
INSERT #T VALUES('6/24/2001 7:05:01.544', '6/24/2001 7:05:01.544')
INSERT #T VALUES('6/24/2001', '6/24/2001')
INSERT #T VALUES('6/24/01', '6/24/01')
INSERT #T VALUES('6-24-2001','6-24-2001')
INSERT #T VALUES('20010624', '20010624') -- this is ISO/international format
INSERT #T VALUES('June 24, 2001', 'June 24, 2001')
INSERT #T VALUES('7:05:01.544', '7:05:01.544')
INSERT #T VALUES('7:05:01.544 PM', '7:05:01.544 PM')
GO

SELECT * FROM #T

Example 2:

id  dt                          sdt
--- --------------------------- ---------------------------
1   2001-06-24 07:36:56.910     2001-06-24 07:37:00
2   2001-06-24 07:05:01.543     2001-06-24 07:05:00
3   2001-06-24 00:00:00.000     2001-06-24 00:00:00
4   2001-06-24 00:00:00.000     2001-06-24 00:00:00
5   2001-06-24 00:00:00.000     2001-06-24 00:00:00
6   2001-06-24 00:00:00.000     2001-06-24 00:00:00
7   2001-06-24 00:00:00.000     2001-06-24 00:00:00
8   1900-01-01 07:05:01.543     1900-01-01 07:05:00
9   1900-01-01 19:05:01.543     1900-01-01 19:05:00