Info on backing up hard drives

[SapphireStar]

Okay, got a letter from my university saying:

This letter is to inform you that because of essential safety tests there will be disruption with your electricity supply and internet connection between the hours of 12 noon to 6.00pm on Wednesday 11th April.

We strongly advise you to back up the hard drive on your PC and to close it down.

Now I dont understand by back up the hard drive. Ive got a memory stick with all my university work saved on it, is that what it means? Also close it down? I dont understand that either.

If anyone could please tell me what either of these things mean I would be grateful! Thank you!

 

[BladeWarrior]

i think it means to make sure that you have the windows profile in a backup disc incase the computer hard drive breaks or malfunctions. or it might mean to add surge protectors because when the powerr goes back up it might just fry every circut in the computer.