Twitter, poised to make its splashy entrance on Wall Street, has helped define modern social networking. But while seeking to establish itself as an Internet powerhouse, it must also prove it can fend off a rising threat from a younger generation of nimble social outlets that offer clever new ways for people to connect and share content.
Among these up-and-comers are Snapchat, WhatsApp, Line, Tumblr, Instagram, Pinterest, Kakao and Reddit. Each has a different take on what social networking should look like -- inventive ways of private messaging and creating content with a rich infusion of images and videos.
These contenders, some from overseas, are attracting millions of followers, some at a greater rate than Twitter, which has been relatively slow to adapt to these newer forms of communication. And most of these services have something that is harder to pinpoint and that money can't buy -- an element of cool, an intangible factor that makes them more appealing than their older predecessors.
Although most of the upstarts are not bringing in significant revenue -- and Twitter has been losing money -- for investors the question is which services will attract the most users and the most advertisers.
"Twitter is unsurpassed as far as text is concerned," said S. Shyam Sundar, a director of the Media Effects Research Laboratory at Pennsylvania State University. "But you see a lot of other social media going into pictures and video, and in that sense, they are behind."
Snapchat, for example, lets people send photos and videos that disappear after they are viewed. On Thursday, the same day Twitter revealed its filing for an initial public offering, Snapchat added a "stories" feature that resembles an ephemeral news feed, letting users stitch together visual narratives and post them publicly, where they can be viewed for just 24 hours.
Snapchat already processes 350 million photos each day, which is not too far behind Twitter's daily rate of 500 million posts each day, even though Twitter is used by three times the number of Americans as Snapchat, according to data from Nielsen.
WhatsApp, a messaging service founded less than five years ago, says it already has more than 300 million active users, compared with Twitter's 218 million.
And Pinterest, which lets people collect and share images of items they like with their friends, is also gaining in popularity. According to comScore, another measuring service, 43 million people in the United States visited Pinterest in August, compared with 62 million for Twitter.
And even as Twitter faces challenges from these younger rivals, it has to compete with Facebook, the largest social network, and other, more established Internet companies.
Twitter declined to discuss its competitors, citing rules limiting what companies can say beyond official filings while a stock offering is pending.
But in its filing, it acknowledged that it competes "against many companies to attract and engage users including companies which have greater financial resources and substantially larger user bases, such as Facebook (including Instagram), Google, LinkedIn, Microsoft and Yahoo!"
Still, the filing promoted what Twitter said was its unique position as a platform for public, real-time conversation, with information that can easily be shared beyond its service. And the company boasted that it was the next step in the Internet's evolution -- a service superior to Netscape's Web browser, Yahoo's portal, Google's search engine and Facebook's closed social network.
Since its founding in 2006 -- a long time ago, in the tech world -- Twitter has essentially stuck to its main vision of letting people share text messages no longer than 140 characters. In its early days, it spent a lot of time tackling engineering problems that kept crashing its service and so, analysts said, it did not spend as much time on creating new products.
But recently the company has been making changes to its service, and some of those changes seem to be responses to what competitors are doing.
For example, it recently modified how it displays photos, making them bigger, so they stand out more in the stream of messages -- more like Facebook.
Although Twitter lost its bid to buy Instagram, a photo-sharing service that Facebook paid $1 billion for, it bought Vine, a start-up that lets people create and upload short bursts of video to their Twitter feed. Vine, a stand-alone app that is integrated into Twitter, has been widely considered a success and has helped Twitter battle Instagram. In fact, Instagram later integrated video-sharing into its own service.
Twitter is also introducing features that deliver information to users automatically, like safety and news alerts and suggestions about people to follow. Building on its lead as the online hub for conversation about television shows, the company may soon suggest shows to watch based on a user's previous interests and activity.
Twitter has also sought to fight competitors through acquisitions. For example, it bought We Are Hunted, a music service, to add new features for users to find music.
Since its start, Twitter has struggled with how to explain itself to new users. Many people sign up but cannot figure out what to post or why. In comparison, sending a photo to your friend or creating a collection of your favorite desserts on Pinterest appears to be more natural and intuitive.
"It's pretty innately easy to figure out what to do with Snapchat or what to do with Pinterest," said Debra Aho Williamson, a principal analyst at eMarketer. "With Twitter, it's not simple to figure out what to do with the service."
Twitter's value over Facebook, said Susan Etlinger, an analyst at the Altimeter Group, is its simple nature. People feel compelled to share their thoughts and reactions to movies, political events and anything else they encounter, forming a kind of "real-time consumer research feed."
"It's quick and immediate and short," she said.
But Twitter does not collect as much demographic or personal information about its users compared with a service like Facebook or LinkedIn. Analysts say that could present challenges down the road as the company competes to send its users relevant advertisements and potentially offer e-commerce.
In its filing, Twitter also mentioned as possible competition the messaging companies Sina Weibo, Line and Kakao, all based in Asia. These pose threats because it will be crucial for Twitter to keep expanding in international markets.
"Twitter is always going to have international competition," said Brian Blau, an analyst with Gartner. "They are already a global player, but there will always be a local incumbent in foreign countries that uses the local language and already has a purpose there."
Twitter still has many aces in its pocket that will help usher the company through its coming trials. For starters, the company has a strong grasp on mobile, which is crucial to staying relevant in a world where smart devices reign supreme. And it has aligned itself with partners like Apple to embed the service in iPad and iPhone software to bolster its popularity.
It also helps that, despite the allure of the competitors' services, they do not yet have much significant revenue, whereas Twitter seems to be figuring out moneymaking strategies, albeit slowly.
Gene Munster, an analyst at Piper Jaffray, cautioned against counting Twitter out too soon. He said that Twitter provided something very different from Snapchat or Line and that there was potentially room for many services.
"The future of social is not going to be a winner-takes-all scenario," he said. "No service can be all things to all people."
"Twitter has found something they're good at, built a brand around it and fortified it," he said. "The real question for the future of the company and their part in social is whether or not they can figure out how to successfully monetize it."
This article originally appeared in The New York Times.