Elon Musk's Twitter rebranded as X. Here's why

The signature blue bird perched atop social media platform Twitter vanished on Sunday as part of a company rebrand under a new name: X.

The revamp marks the latest change enacted by billionaire owner Elon Musk, who stepped down as CEO last month but retained a prominent role in the company.

Promising an AI-fueled expansion of the site's capabilities, X aims to follow the logo change with an ambitious foray into online banking and video messaging, among other areas, CEO Linda Yaccarino said on Sunday.

"It's an exceptionally rare thing -- in life or in business -- that you get a second chance to make another big impression," tweeted Yaccarino, who previously worked as an advertising executive at NBCUniversal.

"Twitter made one massive impression and changed the way we communicate," she added. "Now, X will go further, transforming the global town square."

Here's what to know about X, what makes it different from Twitter and the role of Musk in the rebrand.

What is new about X?

For now, X is a rebranded Twitter -- but the company on Sunday revealed plans to offer users a one-stop shop for many of their online needs.

The aspiration was made public as long ago as last year. Days after acquiring Twitter, in October, Musk tweeted: "Buying Twitter is an accelerant to creating X, the everything app."

Taking a step closer earlier this month, Musk launched an artificial intelligence company called xAI, vowing to develop a generative AI program that competes with established offerings like ChatGPT.

Describing X's goal as "unlimited interactivity," Yaccarino said on Sunday that the company plans to become a hub of online messaging and commerce.

"Powered by AI, X will connect us all in ways we're just beginning to imagine," Yaccarino said.

The best example of what Musk means by an "everything app" is WeChat, a highly popular app in China that serves not only as a messaging and media-sharing platform but also a versatile tool in which users pay friends, purchase products and book reservations, among other uses, analysts previously told ABC News.

Why did Twitter rebrand as X?

The rebrand arrives at a transition period and self-admitted financial difficulty for the company.

Last month, Yaccarino took over as CEO, elevating her as a visible leader alongside Musk, who remains executive chairman and chief technology officer. Musk also serves as CEO of Space X.

Meanwhile, the company has lost 50% of its advertising revenue and faces a negative cash flow, meaning there is more money being spent on expenses than brought in through revenue, Musk tweeted earlier this month.

Prior to its acquisition by Musk, Twitter made the vast majority of its revenue through advertising but many large companies have pulled ads from the platform amid what some have described as a rise of explicit and hateful content.

In addition, X faces a new threat from ascendant social media platform Threads, owned by Facebook parent-company Meta. Threads reached 100 million users within five days, achieving a record as the fastest app ever to do so.

By comparison, Twitter boasted 238 million users before Musk took the company private in October, the company said in an earnings report last year.

What role did Musk play in the rebrand?

Musk's interest in the letter "X" traces back more than two decades.

In 1999, Musk launched an online payments and banking company called X.com, which later merged with PayPal.

Musk repurchased the URL "X.com" in 2017. Now, the domain directs visitors to Twitter.

"Not sure what subtle clues gave it away, but I like the letter X," Musk said in a Tweet on Sunday alongside a photo of him crossing his arms to form the letter.

"And soon we shall bid adieu to the twitter brand and, gradually, all the birds," he added.