This year, cyber criminals flexed their muscles and hacked some big targets, including, some experts believe, American democracy.

According to a CIA assessment, which both FBI Director James B. Comey and Director of National Intelligence James R. Clapper Jr. agree with, Russian-government connected hackers breached the Democratic National Committee's networks and strategically leaked emails to WikiLeaks in an effort to help Donald Trump win the the election by a slim margin.

Dmitri Alperovitch, co-founder and CTO of CrowdStrike, the company that helped identify the DNC hackers as tied to Russian intelligence agencies, said after the attack took place that the breach should serve as an eye-opener for companies and entrepreneurs.

"Organizations, whether they are nonprofits or enterprise, need to be aware that nation-states are coming after them for political espionage, economic espionage, or destructive attacks," said Alperovitch. "We need to be prepared to confront these bad actors. This is the first time since the Revolutionary War where you have Americans fighting governments on U.S. soil. We are doing this in cyberspace, unlike in the Revolutionary War, but it is serious nonetheless."

Hackers revealed over 20,000 emails linked to the DNC, security officials said. Leaked were emails that detailed how the DNC worked against Bernie Sanders' campaign to support Hillary Clinton as the party's nominee. DNC Chair Debbie Wasserman Schultz resigned amidst the fallout of these revelations. The email dumps also resulted in fake news being taken literally, as was the case in "PizzaGate," a fake conspiracy involving a Washington, D.C. pizza place and music venue, Hilary Clinton, and child pornography.

As for lessons for companies and startups, Alperovitch says this attack and misinformation campaign should signal to every business that hackers and spies from Russia and other countries are breaching networks all over the country.

"Assume they are inside your network," he says.

Hackers were not just trying to influence the American election; some hackers just wanted private information. In September, Yahoo! revealed a 2014 cyber attack that affected more than 500 million accounts, one of the biggest breaches in history. In December, the company revealed that it found another leak from three years earlier, that effected one billion users.

This year also showed how hackers can use internet-connected devices to take down major websites, cyber security company Proofpoint CEO Gary Steele says.

In October, 1.5 million infected internet-enabled gadgets, from baby monitors to DVRs, were infected with malware and hackers used this army of bots to wage a distributed denial-of-service attack on websites like Netflix, Twitter, Spotify, CNN reports. Software IT company Dynatrace, which monitors over one hundred websites, estimated that companies lost $110 million in revenue, Dynatrace CEO John van Siclen told CNN.

Steele, CEO of Proofpoint, says 2016 was a year where hackers showed their capabilities in a connected world by hacking the government, political parties, using malware to bring businesses offline, and target individuals. He says it is only going to get worse from here.

"Cyber attacks have become increasing targeted and more widespread," says Steele.

Back in August, a study revealed that ransomware, malware that encrypts a person's personal files and demands money in exchange for returning the data, effects half of all U.S. businesses. From corporations to mom-and-pop shops, cyber criminals are demanding anything from $500 to $10,000, the survey found.

Another development in 2016 is the fact that the U.S. government realized just how serious cyber attacks can get.

During a Congressional hearing on cyber security, experts warned politicians that cyber attacks will one day become lethal, CNN reported in November. "I fear for the day every hospital system is down," Kevin Fu, a computer security professor at the University of Michigan, told the hearing. "This will require some kind of governmental mandate."

In December, President Obama commissioned a report on national cyber security, which he described as a priority for the 45th President of the United States.

"The private sector and the Administration should collaborate on a roadmap for improving the security of digital networks, in particular by achieving robustness against denial-of-service, spoofing, and other attacks on users and the nation's network infrastructure," reads the report. "The urgency of the situation demands that the next Administration move forward promptly on our recommendations, working closely with Congress and the private sector.