A global computer malware attack took over hundreds of thousands of computer systems in just three days and that number is expected to increase when workers turn on their computers Monday morning.

The hackers used ransomware. Once they have access to a company's computer system or a personal device, they can take the computer hostage until a ransom is paid.

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The virus is called WannaCrypt or WannaCry and it will make you want to cry if it ends up on your computer.

"Essentially the objective is to for this individual or organization to pay a ransom before they can use this device or data again," said Tom Hegel, senior threat researcher for ProtectWise, an online network security company.

It's like computer kidnapping.

Hegel said ransomware isn't new, but the hackers' success rate is growing because people and companies around the world are paying to get their information back.

"If you're using any sort of technology that connects to the internet, you're at risk," he said.

You might think you're protected because you don't open up scam emails or download shady attachments, but that's not the only way hackers are spreading malware.

"Nobody has to click anything, you just have to be online and be out of date with your Microsoft Windows patches," explained Hegel.

It's what he calls "drive-by downloads." He suggests making sure computer operating systems are up to date and adding anti-virus software.

If your computer is taken hostage so to speak, the hacker could ask for a ransom of Bitcoins -- anonymous internet currency.

"There's a lot of marketplaces out there on the dark web that allow you to buy either drugs or weapons or any other physical service. Then there are legitimate businesses that are a little bit more on the trending scale to try and accept this as a legitimate payment option," said Hegel.

WannaCry ransom payments range from $600 to $1,000 for the everyday computer user and top hundreds of thousands of dollars for companies.

If you don't pay, you're computer could turn into a glorified doorstop.

"Yes, exactly. You're only option at that point is to pretty much do a factory restore of the entire computer," said Hegel.

In some cases, he says companies like his can find errors in the attackers software and get around the hack.

Hegel says if you use a computer, take these steps immediately:
Update your devices and back up your data and continue to do it weekly either through an external hard drive or through the cloud.

The latest virus gives users one week to pay up or lose all of their files.