As NIKE says; Just do it:

=B1-A1

But you want some theory on it as well I believe. See Chip's page and further links
http://www.cpearson.com/excel/datetime.htm

--
HTH. Best wishes Harald
Excel MVP

Followup to newsgroup only please.

"Lhall" wrote in message news:Ina1b.218262$Ho3.28527@sccrnsc03...
Hope someone can help... I need to get the difference between two times ie:
End - Start.
I guess I need a formula that I can use in Excel that will allow me to enter
the start time, the end time, and then in another cell, get the difference.

So, If I start a job at 7:00 PM (Which is how I enter the info in the cell)
and end the job at say 9:45 PM (entered in the second cell) the third cell
will display 2 Hr 45 min.

I think I am explaining this badly... I guess what I need is to be able to
perform math (Add/Subtract) on Time. I am not familiar with how Excel uses
Time Values.

Begin End Total
7:00 PM 7:30 PM 30 min

Hope someone can help
Larry