• All three major averages rallied to record high closes.
• The Fed held interest rates steady and said it's still expecting three rate cuts this year.
• Reddit is going public after pricing its IPO at $34 a share.

Here are the most important news items that investors need to start their trading day:

1. Three records

The three major averages all rallied Wednesday to hit all-time closing records. The Dow Jones Industrial Average surged 401.37 points, or slightly more than 1%, to close at 39,512.13, while the Nasdaq Composite rose 1.25% to settle at 16,369.41. The S&P 500 closed above 5,200 for the first time, ending the day up 0.89% at 5,224.62. The rallies came after the Federal Reserve interest left rates unchanged, but investors were encouraged by the Fed's projections for the rest of the year (more on that below). Follow live market updates.

2. Holding steady

The Federal Reserve on Wednesday held interest rates at a 23-year high, as expected. The rate-setting Federal Open Market Committee said it will keep its benchmark overnight borrowing rate in a range between 5.25%-5.5%, where it has been since July. But the central bank also signaled in the closely watched "dot plot" that it still foresees three cuts occurring in 2024. Investors had been worried that a series of hot inflation reports could result in even fewer cuts than anticipated. During a news conference, Fed Chair Jerome Powell noted that a strong jobs market wouldn't deter the central bank from reducing rates.

3. Are you Reddit for it?

Reddit priced its initial public offering Wednesday at $34 a share, valuing the company at close to $6.5 billion, near the top of the expected range. The social media company will debut Thursday under the ticker "RDDT." It's the first major social media name to go public since Pinterest's debut in 2019 and one of the very few venture-backed tech deals of the past two years. Reddit set some shares aside for its power users and invited them to participate in the IPO, but several of them told CNBC's Jonathan Vanian that they're declining the offer, citing a rocky relationship with management and concerns about the company's business.

4. Micron pops

Another company is benefiting from the artificial intelligence boom. Shares of Micron popped more than 16% on Thursday morning after the company reported second-quarter earnings results Wednesday that beat analysts' expectations and offered rosy guidance. It brought in earnings per share of 42 cents adjusted versus a 25 cent loss expected by LSEG, formerly known as Refinitiv, and revenue of $5.82 billion vs. $5.35 billion expected by LSEG. Micron provides memory and flash storage for computers, phones and data centers, which are used to power the influx of new AI software.

5. The future of ESPN

The business model for Disney's ESPN appears to be crumbling. The world's largest all-sports network has relied on cable subscription fees for more than 40 years, but more and more Americans are opting to cancel their cable TV. To figure out what comes next for the sports media giant and how it plans to stay relevant, CNBC's Alex Sherman spoke with multiple current and former Disney and ESPN executives for the digital documentary "ESPN's Fight for Dominance." "The industry is in a transition phase right now," ESPN Chairman Jimmy Pitaro said in an interview.

— CNBC's Samantha Subin, Jeff Cox, Jonathan Vanian, Leslie Picker, Ashley Capoot and Alex Sherman contributed to this report.

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