X (formerly Twitter)

The idea for Twitter came from Jack Dorsey during a brainstorming session at podcasting startup Odeo in March 2006. The first tweet was sent by Dorsey on March 21, 2006: "just setting up my twttr." The name Twitter was chosen because it described the short bursts of inconsequential information that birds make. Within four years, Twitter had become the nervous system of breaking news worldwide.

Jack Dorsey was removed as CEO of Twitter in October 2008 by co-founder Evan Williams, who took over the role himself. The official reason was that Dorsey spent too much time on personal interests — including fashion design and yoga. Dorsey went on to found Square (later Block). Williams later said firing Dorsey was simultaneously the right decision and the wrong decision.

Elon Musk began buying Twitter shares in January 2022, eventually accumulating a 9.1% stake. He offered to buy the entire company for $54.20 per share — $44 billion total. Then tried to back out. Twitter sued him. A Delaware court ruled against Musk. On October 27, 2022, Musk completed the acquisition, walked into Twitter headquarters carrying a sink, fired approximately half the company within 48 hours, renamed it X, and replaced the iconic bird logo with a stylised X. Brand consultancies estimated the rebrand destroyed $4 billion in brand value overnight.

Musk renamed Twitter to X in July 2023, describing his vision as a WeChat-style "everything app" combining payments, messaging, news, and social media. Advertisers fled over content moderation concerns. Revenue fell by an estimated 50% from Twitter's pre-acquisition levels. Musk responded by suing advertisers for what he called an illegal boycott. Linda Yaccarino, hired as CEO to rebuild advertiser relationships, resigned in July 2025.

In March 2025, Elon Musk's AI startup xAI formally acquired X in an all-stock deal that valued X at $33 billion — $11 billion less than Musk had paid for it three years earlier. xAI, which had been valued at $80 billion, absorbed X to combine its Grok chatbot with X's 600 million monthly users and real-time data. The combined entity, called xAI Holdings, was worth approximately $113 billion. Musk had effectively bought Twitter from himself — using a company he had founded specifically to compete with OpenAI.