Twitter is a "microblogging" service, where users post 140-character "tweets". They can be mundane reporting on their life, a wry one-liner, or the start of an Internet campaign that will snowball and end up with international media coverage. Really, for just 140 characters, there's lots of potential.The site's open, public API allows for its adaptation and use on many different platforms. Android, iPhone, browser extension, desktop software, mobile phone... you can tweet from just about every device going. Hell, you can even monitor tweets with a typewriter!The site is popular and trendy. The real-time search function, which allows you to search all (public) tweets being made for any word or phrase you wish, is one of the most popular aspects of the site. This is combined with the "trending topics", a list of the ten most popular topics at the moment, based on how much they're being tweeted about. This list of trending topics will almost always include Justin Bieber, at least until Twitter supposedly banned his name from trending and his fans made "let Bieber trend" a trend instead. When they were no longer able to do that, they resorted to trends like "Bustin Jieber". Still, Justin Bieber related topics trend almost every day, and in 2012, they were joined by topics about British-Irish boy band One Direction.Twitter has gotten a lot of media attention. Major events tend to be covered rapidly through the system, and it has become hip in Hollywood for a celebrity to have a Twitter account. Twitter nicknames get given out like email addresses. In fact, despite the Biebermania, Twitter appears to be the first Friending Network type site (aside from work-oriented LinkedIn) in which thirtysomething media professionals outnumber teenagers.You can follow TVTropes on Twitter, or browse TV Tropes Twitter-style with the Laconic Wiki.
Twitter provides examples of:
Awesome, but Impractical: Streaming is avalilable on some mobile clients, but it will eat through your battery very quickly.
Be Careful What You Say: Big Brother Is Watching—not to mention the rest of the world. The number of athletes and celebrities that have gotten themselves into hot water because of controversial or offensive tweets is downright staggering.
Early in the 2012 Olympic Games, three athletes were singled out for controversial and/or racist tweets. Two of those athletes were summarily expelled from the Games.
Beige Prose: Though it's still impressive how much you can say within 140 characters. Japanese and Chinese users can put quite an amount of information into 140 characters due to how their language works, though.
Character Blog: Many fictional characters have a presence as well. Most are roleplayed (look for the telltale "[RP]" or "role-played" somewhere in their profile), but some are 'genuine' in the sense that their origin company controlled them. You can see a list of some of them here.
Fangirl: Many. Why do you think Justin Bieber never stops trending?
As of August 31st, 2010, this has happened to any Twitter application only using Basic Authentication.
The new OAuth implementation is broken itself. It basically requires the identification keys to be hard-coded into the clients, and Twitter has announced they are going to be de-authenticating compromised keys. And, yeah, the keys to the official Twitter client for Android are a string dump away.
As if they weren't already suffering from an overly severe buttmonkeydom, Zune users had to wait 2 weeks for their official app to be fixed after the switchover.
As of June 7, 2013, any app that does not use the current version 1.1 API is dead, as Twitter permanently shut off API 1.0. While some developers will take notice and update their clients to use the new API, you may as well uninstall any long-abandoned clients that you use.
After Paul Chambers lost his appeal against his conviction for tweeting a joke about blowing up Robin Hood airport, people began retweeting the original message en masse with this attached as a hashtag.
During the protests in Iran in 2009, lots of users set their location to Tehran in an effort to thwart the country's censors.
Nerf: With version 1.0 of the API, you can constantly refresh your timeline, so long as you have API calls (which you are allowed 350 of per hour) left. However, version 1.1 aims to gimp this; you can only refresh your timeline, mentions, and direct messages 15 times per 15 minutes each. This is not a problem if you use Twitter lightly, or use a client that streams tweets (which will not consume API calls), but if you are very active and/or follow a lot of people, particularly on most mobile clients, and especially if you tend to accidentally refresh more times than you try to, it's very easy to get "API limit exceeded" errors.
Inverted by old media's reaction to Twitter. They are crazy for it, and pretty much every old-media organization had set up multiple Twitter accounts (plus dozens of individual personal accounts for employees) before it even really caught on. See also Small Reference Pools, below.
Played straight by younger media — for example, read the hilariously hypocritical message board rants against it. Boo, any interpersonal e-communication that isn't e-mail... wait...
Obvious Beta: Users became very familiar with the "Fail Whale" seen in the page image. The site suffers a lot of smaller hiccups frequently.
Refreshing your timeline, interactions, and direct messages is limited to 15 times per 15 minutes each. If you tend to refresh your timeline a lot on a mobile device, this can happen easily, especially if you accidentally make extra refreshes. Other actions, such as refreshing lists, searches, or a user's tweets, have similar limits.
Tweeting too much within one hour or so (usually on the order of about 60-70 tweets) will disable you from tweeting again for a while, usually an hour at most. This is known amongst many users as "Twitter jail", and usually happens as a result of rapid-fire conversations with other users or livetweeting events. Generally, if you see someone with a six-digit tweet count, chances are they've been jailed at least once. Outside of jailings, each account is limited to 1,000 tweets per day.
Private messages, however, have a cap of 250 messages sent per day.
Please Select New City Hashtag: Sometimes hashtags collide. For instance, #btv had been used primarily for discussions pertaining to Burlington, Vermont (from the city's airport code), until a massive influx of Arabic-language posts in early 2011 referring to Bahrain Television, after which the Burlington folks switched to #bvt.
The BBC, in particular, is obsessed to an indescribable degree with Twitter. Any news that can possibly be related to anything to do with technology or society in general, never mind the Internet, is determinedly dragged around by its news interviewers to the subject of Twitter, often leading to the more net-savvy interviewees becoming bewildered.