Redhats are neither whitehat nor blackhat, but a mix of both. Adapted from early RPG games where white mages used healing, protective "good" spells, black mages used elemental, destructive "bad" spells, and red mages had a selection of spells from both.

Examples of redhats:
- People who are hired to find security holes in a network, do so, but create new exploits in order to take advantage of later.

- Someone who breaks into a secure area and then informs the owner that they can fix the security holes if they hire them.

- Someone who works in network security and uses their job experience to take advantage of exploits either within their own company or elsewhere.
This redhat is offering to fix our security holes for $5,000.
by Jon Byrd October 28, 2005
There's lot of definitions for red hat, and is often used without explanation. It's all about context.

Most recently and most frequently it's a reference to Donald Trump's infamous "Make America Great Again" MAGA red hat.

Ironically on the left wing, red is the traditional color of communism. The same red beret worn US airborne troopers were also worn by militant socialists or union organizers. Hugo Chávez, president of Venezuela from 1999 until his death in 2013, was called a red hat.

Pre-World War II, pacifists and union organizers were called red hats. The "Red Hat Acoustic Music Club" celebrates this usage.

Red hat can be used as a reference to the Bloods criminal gang, such as Jay-Z "What's Free" song.

Red-hats / red caps are malevolent spirits found in the lowlands of Scotland. Their red hats would frequently re-dyed in human blood. It's associated with violence and vampirism. It the meaning of AFI's song "Red Hat"

The Linux computer software is called "RedHat" because its creator Marc Ewing wore a red hat.
Jay-Z "What's Free"

“No redhat, don’t Michael and Prince me and Ye
They separate you when you got Michael and Prince’s DNA"

AFI's song "RedHat"

"Can’t remember days, the days we posses, only the day she left.

I see her in the crucifix, my mind begins to slip. My love had fallen right to a T.

Then I close my eyes and the tears begin to run, the nightmare has just begun.
by Kingdragonfly July 8, 2019
A supporter of President Donald Trump supporter, because they wear red hats.
Redhats were shitposting on Reddit again.
by ddrevolution June 2, 2017
A fervent supporter of Donald Trump. Redhats typically reject all reputable news sources as "lame stream media" and only believe what they hear from chain emails, Trump himself, and fake news articles on Facebook.

Typically incoherent and bigoted, redhats believe they can win any argument by repeatedly shouting "snowflake" and contesting basic facts.

Named after the infamous "Make America Great Again" headwear, on the pattern of brownshirt.
Don't make racist jokes, Dad, you sound like a goddamn redhat.
by Nameless_Steve December 7, 2016