An uninterrupted power supply (UPS) is a fairly inexpensive safeguard to protect your computer from unexpected power loss. Even if the battery only lasts for a few minutes, it gives you those precious moments to save your work and properly shut down your computer. So what happens if you don't have a UPS and you just let the power company play God with your computer?
Also consider what will happen if you're working on a file and hadn't saved your changes in a while (learn CTRL-S and use it frequently) and the power goes out. All that hard work goes out the window, and motivation to retype it all also goes out the window.
Then consider that your operating system might become corrupted. Most of the time your computer will be able to boot back up from an unexpected shutdown, but not allowing it to gracefully close things out raises the potential for error. Important system files can become corrupted, among other not so good for your operating system things.
So spend a few bucks and plug it into a UPS.
MORE ABOUT UNINTERRUPTIBLE POWER SUPPLIES ON APARTMENT THERAPY:
• How Do You Hide a UPS Battery in the Office?
• It's Time You Updated These 6 Devices In Your Home Office
• UPS vs. Surge Protector