How can I save files to hard disc and USB memory stick at the same time?

Like you mean RAID. but for that you need two harddisks and a motherborad that Supports RAID tecnology and most motherboards that have it (I cant comment on newer ones). But use RAID u need as I underand it 3 harddrives. One to run the operative system. and two extra to run this function. And they perferable need to be of same size and brand. If they are of differnt size u only can use the smaler size on the bigger one. I don´t know about mixing brands one...but i guess they can be a little bit differnly configurated. I can´t see how this would even be possible. The USB stick is not even a harddrive. And inpobobly to acually using a 1/2/4/8/16 GB USb stick U only could u the same on the hard drive. also a USB is slower than a harddrive. And for that matter u need a desktopcomputer for using all this. I have never seen this funktion in a laptop. Becouse when move the laptop u need to move the external harddrives too. U can´t unplug the harddrives when you use RAID. it not inpossible to achive but you laptop would be needed to be shut down to be moved. And with DISK MIRRORING with databases your after the speed benefits. not two exaact alike harddrive. And running this risks craching both at the same time. I never crashed anythings with Raid but I was not running a on-line database that in 24/7 years on end. And you need to backup system anyway from time to time. And I the the database need to go offline for this. The only sollution to your prob that is to copy by manually alot more than. Use a DVD-RW to backing up your files often. , The only thing i can see to your problem is some kind of Syncrination software. I know a USB stick can be used

It depends on your operating system. I don't think you can save a file to a hard disk and a USB stick at the same time on a Windows based computer, But there might be a way if you have a Mac. For the Mac you can copy the USB device icon to your desktop AND hard drive, then try to save a sample file to the USB device icon on the desk top. The file should be in the desktop USB device icon. Now, open up the hard drive and find the copy of the USB device. Look inside, and you should have a copy of the file in there as well. If not, then you have to use the Mac's Automator feature which lets you create a set of directions to save a file to your hard disk and your USB device at the same time. Hope this helped some.