7 things you need to know about the huge CrowdStrike IT outage

• A widespread IT outage linked to a CrowdStrike update hit global operations on Friday.
• The outage caused travel chaos, affected hospitals, and even took out some broadcasters.
• The issue was caused by a defect in an update for Windows. 

The world has been hit by one of the most widespread tech outages in history.

The Friday outage, linked to cyber security firm CrowdStrike, affected operations around the world and has been compared to Y2K. Flights have been grounded, some medical procedures and appointments were canceled, and TV networks were taken off the air.

"This is basically what we were all worried about with Y2K, except it's actually happened this time," Troy Hunt, an Australian web security expert, said in an X post. "I don't think it's too early to call it: this will be the largest IT outage in history."

Here are seven things you need to know about the mass outage.

1. A single update was responsible

The issue was caused by a "defect" in an update for Windows, according to CrowdStrike.

Shortly after the issues emerged, CEO George Kurtz said they were not caused by a cyberattack. In a post on X, Kurtz said customers were affected "by a defect found in a single content update for Windows."

He added the issue had been "identified, isolated, and a fix has been deployed."

2. Lots of flights were grounded or delayed

The outage brought some air travel to a standstill, or a crawl.

Major airlines including American, Delta, and United grounded many flights, and passengers faced long waits in airports.

Disruption also extended to Europe. The continent's largest airline, Ryanair, advised passengers to arrive early as the outage caused "disruption across the network."

Problems for travelers are likely to last for days as airlines and airports struggle to get operations back to normal amid the busy summer vacation season.

3. Trains and gas stations were also affected

Those traveling by rail or road did not entirely escape the travel chaos.

In an X post, the New York subway announced that train arrival information was unavailable for many trains.

In the UK, train networks were also disrupted. The National Rail website cited IT issues across the entire network: "Some train operators are unable to access driver diagrams at certain locations, leading to potential short-notice train cancellations. Additionally, other key systems, including real-time customer information platforms, are also affected."

Some Speedway gas stations across the US closed because digital gas pumps failed to work, and others were not accepting payments, an employee told BI.

4. Hospitals and surgeries were affected

The tech issues also disrupted medical care.

The National Health Service in the UK told BI an issue with an appointment and patient record system was "causing disruption in the majority of GP practices" on Friday.

In Germany, two hospitals canceled elective operations scheduled for Friday, Reuters reported.

5. Governments and federal agencies got involved

Governments and their agencies around the world were quick to address the chaos.

The Department of Homeland Security said in a post on X: "The Department, and the Cybersecurity and Infrastructure Security Agency (@CISAgov) are working with CrowdStrike, Microsoft and our federal, state, local and critical infrastructure partners to fully assess and address system outages."

The UK government was also due to hold an emergency meeting to discuss the outage later on Friday.

6. Some broadcasters fell off the air

Media companies were also affected by the tech issues.

Sky News in the UK was briefly forced off air and played archive footage. In Australia, which appeared to be badly hit by the outage, outlets including the ABC were unable to broadcast on radio or TV.

7. Expect disruption to continue

As companies struggle with the fallout, customers may experience continued disruption throughout the weekend and beyond.

According to BBC News, more than 3,300 flights were canceled on Friday, which means airlines will be left with many stranded passengers to deal with and planes in the wrong place. This is highly likely to affect flights in the coming days.

It may also take some companies longer to recover from the outage than others.

James Bore, a cybersecurity expert at Bores Group, told Business Insider that the issue couldn't be fixed automatically and required a manual reboot. That could take a significant amount of time if an organization has many PCs.