Newsmax, the right-wing cable news channel, has been on a roller coaster since its shares started trading on the public markets on Monday.

The stock rocketed to a high of $279 on the New York Stock Exchange this week, a price that briefly valued the company at more than $20 billion. On Wednesday, the stock crashed to $133, valuing the company around $15 billion by midafternoon. That puts it ahead of U.S. Steel, which is valued at roughly $9.5 billion.

The wild stock market debut was just the latest unexpected twist for Newsmax, started more than a decade ago as a long-shot challenger to more established cable news channels like Fox News, CNN and MSNBC.

Here’s what you need to know:

Newsmax is the brainchild of Chris Ruddy, a former New York Post reporter with ties to President Trump’s social circle in South Florida. Mr. Ruddy, 60, founded Newsmax in 1998 and has since built it into a conservative media darling, with a cable channel, a magazine and a digital subscription service, Newsmax+. Like many other conservative media businesses, Newsmax sells health supplements, which it calls its “nutraceuticals business.”

The company, which is known primarily for its cable channel, has reliably conservative programming, with anchors including Greg Kelly, a former Fox News host, and Michael Savage, a right-wing radio host. The channel is carried on most major cable and satellite providers, including DirecTV, Dish, Comcast, Charter and Verizon.

The channel made its stock market debut on Monday and has benefited from the investor enthusiasm in companies associated with Mr. Trump, such as the Trump Media & Technology Group, the parent company of his Truth Social platform.

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