is there a program that will startup my computer automatically when it's been shutdow
 

i want my computer to function as an alarm clock, i want it to be shut down but start up automatically at a desired time (i'll also have tomboy notes display reminders of what i need to do for the day) this would be a great program and i appreciate the help from this friendly community

With ABSOLUTELY NO SPECS I can only say...

There MAY be such a setting in the BIOS... take a look.

:D

From my 2p...
All the devices with alarm clocks (phones, smartphones, electronic watches etc) are constantly on. That's why they can start producing some noise at set time.
If computer is shutdown, there are no programs running in it. Except for some motherboard-hardware-embedded. Like clocks counting.
Therefore, your question is nether Linux nor any other system related. As you were told, you might find an answer in your hardware (BIOS) configuration, but I am in doubt.

Debian newbie here.

I'm not sure, but I thought that I read something about Scheduled Shutdown & Startup.
I'm not exactly sure of the function and capabilities. In fact it may have been in my BIOS.

Only if your BIOS supports it. Your BIOS may have a wake on LAN, or wake on ring.

@darkduck, I had a Siemens mobile phone, and the alarm would still go off even if the phone was switched off.

In short, your computer cannot run any software, when its off. When its off, its OFF any only some basic functions still operate (such as the clock and maybe wake on lan, etc). But no operating system is running.

I use a BIOS setting to do pretty much exactly what the OP is after. I suspend-to-disk last thing at night and the BIOS setting restarts the PC at 0600 every morning.

All mobile phones are not actually off when they are "off". They are still working, and even on-line at this time. Unless you get the battery out.
I had similar tricks with Nokia.

Many BIOSes can start a computer at a schedule, but the computer must be Hibernated (to disk or memory), not off. At least I have not seen a BIOS being able to wake up a computer in totally off state. There is nothing to prevent that though as there is still voltage on the main board when the computer is off. But it seems never have been implemented.

I must say that I have been extremely unsuccessful in hibernating my Linux computer and start it up again.

jlinkels