Declare @var????

I am trying to get a grasp on the Sql Stored procedures it seems i dont really understnad what DECLARE @Date DateTime means??? I mean i think it means that i am just declaring a varible name Date that will hold a DateTime Value??? is that correct or is it more to it????

CREATE PROCEDURE dbo.Tracking_GetStatus
AS
DECLARE @Date DateTime
DECLARE @Begining DateTime
DECLARE @Ending DateTime

SET @Date = GETDATE()
SET @Begining = DATEADD(ss,(DATEPART(ss,@Date)*-1),
DATEADD(mi,(DATEPART(mi,@Date)*-1),
DATEADD(hh,(DATEPART(hh,@Date)*-1),@Date)))
SET @Ending = DATEADD(ss,-1,
DATEADD(dd,1,DATEADD(ss,(DATEPART(ss,@Date)*-1),
DATEADD(mi,(DATEPART(mi,@Date)*-1),
DATEADD(hh,(DATEPART(hh,@Date)*-1),@Date)))))

SELECT
Vehicl,
UpdateTi
XCoord,
YCoord,
Status
FROM Track
WHERE UpdateTime >= @Begining
AND UpdateTime <= @Ending
RETURN


GO