Skype is logging off.

On Friday, Microsoft announced that the 21-year-old calling and messaging service will shut down May 5. The software company is encouraging Skype users to migrate to its free Teams app.

Skype won attention in the 2000s for giving people a way to talk without paying the phone company, but stumbled in the mobile era and didn’t enjoy a major resurgence during the pandemic. Some people have forgotten that it’s still available, given the many other options for chatting and calling.

“We’ve learned a lot from Skype over the years that we’ve put into Teams as we’ve evolved teams over the last seven to eight years,” Jeff Teper, president of Microsoft 365 collaborative apps and platforms, said in an interview with CNBC. “But we felt like now is the time because we can be simpler for the market, for our customer base, and we can deliver more innovation faster just by being focused on Teams.”

Over the next few days, Microsoft will start allowing people to sign in to Teams with Skype credentials, and Skype contacts and chats will transfer over, according to a blog post. People can also export their Skype data. The company will stop selling monthly Skype subscriptions, and users with credits can keep using them in Teams.

“This is obviously a big, big moment for us, and we’re certainly very grateful in many ways,” Teper said. “Skype pioneered audio and video calling on the web for many, many people.”

It’s one of the most enduring digital brands.

In 2003, Janus Friis and Niklas Zennström, who previously co-founded peer-to-peer file-sharing program Kazaa, launched Skype in Estonia with help from a band of former classmates with zero experience in telecommunications. Originally, Skype was a tool for people to call one another online for free. The quirky name stood for “sky peer to peer,” a reference to the service’s underlying voice over internet protocol, or VoIP, architecture.

Skype caught on quickly. By 2004, there were 11 million registered users. By the time eBay announced a plan to buy Skype Technologies SA for $2.6 billion in 2005, the user count had reached 54 million, and Skype was anticipating $60 million in annual revenue, thanks to payments from those who wished to call mobile phones and landlines.

Meg Whitman, eBay’s CEO at the time, envisioned that Skype would help people more quickly complete sales of products, especially costly ones, by connecting buyers and sellers. And eBay could charge extra for such calls. Skype users across the world could discover eBay and PayPal, too. The deal was completed 29 days later.

Under eBay, Skype’s user number grew, crossing 405 million by 2008, and communications revenue rose. But then Whitman stepped down as CEO, making way for former Bain executive John Donahoe, who didn’t think eBay’s core businesses were benefiting from the Skype transaction.

In 2009, the economy was in recession, eBay’s sales growth had turned negative, and the stock price was lower than it had been since 2001. In a statement that touted the release of a Skype app for Apple’s iPhone, Donahoe announced that eBay would launch a Skype initial public offering as part of a separation.

But eBay never filed for a Skype IPO. Four and a half months after declaring the IPO strategy, eBay said it had reached an agreement to sell Skype to an investor group led by Silver Lake in a deal worth $2.75 billion. The online auction operator received a 30% stake in Skype’s buyer. Under the investor group, Skype filed for an IPO, but that didn’t come to pass, either. Microsoft wound up acquiring Skype in 2011 for $8.5 billion, with eBay receiving over $2 billion.

“Microsoft and Skype together will bring together hundreds of millions or, as Tony said, billions of consumers and empower them to communicate in new and interesting ways,” Microsoft’s CEO at the time, Steve Ballmer, said at a press conference, referring to comments earlier at the event from Skype’s leader, Tony Bates. By that point, 170 million people were using Skype each month. Ballmer aimed to integrate Skype with several Microsoft products, including Lync, Windows Live Messenger, Windows Phone and Xbox video game consoles. Microsoft also got Skype running on its Azure cloud infrastructure.

Skype did not manage to accumulate a billion active users, though.

Apple’s native iMessage and FaceTime were picking up traction on iOS devices. In 2014, Facebook bought WhatsApp, a mobile messaging app, and months later, users gained the ability to place calls across borders. WhatsApp took off globally. So did Tencent’s WeChat.

Skype, meanwhile, implemented multiple redesigns and faced criticism from devotees. In 2016, Microsoft introduced Teams as a distinct “chat-based workspace” for organizations with Office productivity software subscriptions that would compete with Slack, which was then an emerging startup.

When Covid came and pushed people to work and study from home, Zoom, originally conceived for business use, became a consumer favorite for holding video calls. People could also connect on video through services from Cisco, Facebook and Google. Skype did see a usage bump, but Microsoft put major engineering resources behind Teams for companies, governments and schools, and the investment paid off. Analysts began concentrating on the number of Teams users that Microsoft would disclose, with the figure exceeding 320 million in 2023.

As for Skype, Microsoft’s current CEO, Satya Nadella, hasn’t mentioned it on an earnings call since 2017.

In 2023, Microsoft said Skype had 36 million daily active users. That was down from 40 million in March 2020. Teper declined to talk about how many people use the service today, but did say the number of minutes consumers have spent on Teams calls increased four-fold in the past two years.

“I think a good write-up of the history of the thing would mark the shift to mobile and cloud as a significant change in the communications category,” Teper said.

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