Hi, from CNN. I'm Emily Williams with the five things you need to know for Friday, July 19th.

A massive tech outage continues to cause disruptions around the world today, a full recovery could be a long arduous process.

The outage has been felt across multiple sectors, from airlines to banks to health care systems and emergency services.

One expert says it could be the largest IT outage in history.

A source of the chaos was, at least in in part a software update for Microsoft Windows

that was pushed out by the cybersecurity company Crowd Strike.

CNN Aviation analyst Miles O'Brien says there are lessons to learn from this, especially for airlines,

which canceled more than 2,500 U.S. flights today.

It shows a little bit of a blind spot on the part of the airlines in the sense that they're not taking

that ethos of redundancy outside what is strictly mission critical for safety.

Hopefully there is a lesson learned here because we're all kind of realizing what a house

of cards this is.

More congressional Democrats joined a growing course of lawmakers today calling on President Joe

Biden to step aside. There are now more than 30 Hill Democrats publicly

asking Biden to drop out. A Biden aide told CNN there's a quote growing sense

that it's game over for Biden's candidacy despite continued messaging from

his campaign that he'll stay in the race.

In an interview with W NYC today,

House Minority Leader Hakim Jeffries

skirted repeated questions about whether Biden

is the best candidate to defeat Trump. The decision is one that can be made by only a single individual,

the president of the United States of America.

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