Humans are great at creating myths. From Marduk and Zeus to unicorns and mermaids, there's no end to what we can imagine. That's true even with technology.

There's old tech advice that no one questions, half-remembered instructions you just keep doing, misunderstood terms and more that you believe to be true.

I'm going to tackle some of these tech myths and set the record straight. 

1. Just delete files you no longer want

I'm sure you know that if you delete a file on a PC or Mac, it doesn't really go away. The file merely sits in the Trash or Recycle Bin until you empty it.

But even after you empty the trash, the file still isn't really gone. It's sitting on your hard drive until another bit of data covers it up. Until that happens — which can be minutes or months — anyone with a little time and a free program like Recuva can get it back.

If you really want to wipe out a file or folder, you need a program like Eraser for Windows or Permanent Eraser for Mac. These programs will overwrite deleted files several times so it can never be recovered. 

Need to wipe more than just a file? Click here to learn how to completely wipe your personal data from a computer, tablet or smartphone before you sell or give it away.

2. An LED TV is better than an LCD TV

You're shopping for a new TV and you have a choice: LED or LCD? What's the difference?

Actually, there is none. LED and LCD refer to completely different parts of a TV.

LCD, or liquid-crystal display, refers to the technology in the TV screen. Its competitors are plasma, which is just about gone, and OLED, which is amazing but still really expensive.

LED, or light-emitting diode, refers to the LCD screen's backlight — or what makes the light that lets you see the image. Backlights used to be cold-cathode fluorescent lamps, but now every TV uses LEDs because they're more energy efficient and they last longer.

So, in the end, it's really no choice at all; every TV is an LED LCD TV.

But there are plenty of TV features that could make a big difference in quality. Click here for the full scoop on what to look for in a TV when you're shopping.

3. It's OK to leave your laptop plugged in all the time

I find it funny that so many people buy laptops and then always leave them in the same place just like a desktop computer. That means they always leave them plugged in as well.

Unfortunately, that can be a problem for the laptop's battery. Fortunately, overcharging isn't so much of a danger anymore.

Most modern laptops have circuitry that keeps the battery just under 100 percent when it's plugged in. That means there's less chance the battery will overheat and catch fire.

However, lithium-ion batteries — like the ones in laptops — last longest when they stay between 20 percent and 80 percent capacity. When they spend a lot of time above and below those percentages, it shortens the battery's life.

Also, a battery that's charging while the laptop is running will be hotter than usual. That shortens the overall battery life.

So if your laptop is always sitting in the same place, it's a good idea to unplug it every now and then and let the battery take over. Or you can take the battery out and leave it plugged in all the time.

Click here to learn more about battery maintenance and safety for laptops and other mobile gadgets.

4. Always shut down your computer at night

This myth goes all the way back to the early days of computers. Back then, computer parts — especially hard drives — wore out much faster than they do today.

So, the idea was that to make your computer last longer, you should always shut it down at night. And many people still say that.

Of course, modern computers have more robust parts, which means you can let them run for years with little to no problem.

This mostly comes down to preference. If you want your computer to do things like back up, update or perform other intensive tasks, you can schedule them at night while you sleep.

If you're concerned about saving energy, turn it off. Or you can use one of your computer's many power-saving modes, which are more convenient for getting it going again in the morning.

5. You'll know when you have a virus

Many people think viruses work like the one in the 1996 blockbuster "Independence Day." When it triggers, you get a laughing skull and crossbones on your screen. Or maybe you'll see regular computer glitches, missing files or other signs something is wrong.

Viruses like that do exist, but many newer computer viruses do just the opposite.

They hide so well, you never know they're there. That way, they can steal your information, send spam, work with other infected computers to attack corporate or government networks or perform other sneaky tricks without you noticing. Click here for the five signs you have a computer virus.

That's why you really need to have up-to-date security software installed and running. If you don't already, here are some of my favorite free options.

Copyright 2014, WestStar Multimedia Entertainment. All rights reserved.

On the Kim Komando Show, the nation's largest weekend radio talk show, Kim takes calls and dispenses advice on today's digital lifestyle, from smartphones and tablets to online privacy and data hacks. For her daily tips, free newsletters and more, visit her website at Kim also posts breaking tech news 24/7 at