There is no 'must'. It is advisable.
Saves power, reduces wear on the computer, reduces the risk of fire when left unattended.
Technological advances in computer circuitry - mean they use far less than they used to. Left plugged in (but switched off) a computer uses less electricity over a year, than a 100 Watt light bulb would that's on !
You may have chose standby by accident, because when you put your computer on standby, it looks like it is turned off, but when you hit the spacebar it either resumes or goes to the login area where you will have to enter your password again
Yes, surge strips will help save money on electrical bills if they are switched off after each use. Anything unplugged after use in a home will save money.
you must use some cheese
press the off button
Do check if all the computers are switched off or turned on correctly and ensure all wires are correctly plugged. Don't put liquids near computers and avoid leaving the computers on when not in use.
To print documents off of a computer...
You cannot use the computer, period, if the power is off, let alone an instant messenger application.
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Its really must to use softwares for a virus free systems.I use to follow 5 important steps for protecting my computer.These steps are 1.Keep my immunet antivirus up-to-date. 2.Protect my identity online 3.Get my computer switched off while not in use 4.Never open unknown email attachments 5.Last but not least always use to download softwares from trusted sites.
No, use the power button to turn off your computer. USB is best because You can unplug and plug the keyboard back in without your computer turning off.
I have switched over my light bulbs, unplugged a bunch of things when they are not in use and I turn off my computer now when I'm not using it. However minimal these things may seem, I have seen savings on my electric bill already.