Twitter is an online social networking service and micro-blogging service that enables its users to send and read text-based posts of up to 140 characters, known as "tweets". It was created in March 2006 by Jack Dorsey and launched that July. The service rapidly gained worldwide popularity, with over 500 million active users as of 2012, generating over 340 million tweets daily and handling over 1.6 billion search queries per day. Since its launch, the Twitter website has become one of the top 10 most visited on the Internet, and has been described as "the SMS of the Internet." Unregistered users can read the tweets, while registered users can post tweets through the website interface, SMS, or a range of apps for mobile devices.
As of April 2012, Bieber's Twitter account (@justinbieber) is the second most popular celebrity account behind that of Lady Gaga. By mid-April 2012, he had over 20 million followers. His follower acquisition is one new follower every other second. His popularity on Twitter at one point accounted for three percent of all Twitter related traffic, with a Twitter employee commenting that "racks of servers are dedicated" to Bieber. This resulted in over 180 million page views for the service each month. Bieber was frequently a trending topic on Twitter when the feature first launched because his fans frequently discussed him on the network. and was named the top trending star on Twitter in 2010; Klout gave his account a score of 100.
The size of Bieber's and Gaga's follower bases are cited as a reason why marketers should pay attention to Twitter: with an ability to reach millions of people with a single tweet. 8.3% of tweets mentioning "bieber" were semi-automated and probably Twitter related spam. Research done about Twitter and the 2011 Egyptian revolution includes Bieber as he made tweets about the topic at a time when he had roughly 8 million followers. His multiple tweets resulted in 32,000 responses each, which made Bieber's Twitter account one of the single largest nodes for discussion about the uprising on Twitter.
In March 2012, Bieber fans launched an unsuccessful attempt to unseat Lady Gaga as the most popular celebrity on Twitter. Neither Bieber nor Lady Gaga discussed their mutual fanbase's campaigns on Twitter. Justin surpassed Lady Gaga for having the most followed person on Twitter in January 2013. In early November 2013, Katy Perry surpassed him for having the most followers.
- On September 2, 2009 Justin Bieber was a trending topic for one of the first times and he was thrilled.
- When Justin's twitter was hacked, the US police got 15,000 calls from beliebers.
- Twitter blocked 'Justin Bieber' from trending topics because he was trending for three months.
- September 2, 2009: Justin Bieber
- April 1, 2011: #AlwaysSayNever
- October 8, 2011: #9DAYS
- November 18, 2011: #ThinkinBoutYou
- January 4, 2012: #chrisbieber 
- January 4, 2012: Justin Is A Sexpanther 
- September 24, 2013: #WelcomeJustinToThailand
- July 8, 2018: Hailey
- July 8, 2018: Justin Bieber
- July 23, 2018: #NoBrainer
- July 27, 2018: #NoBrainerOutTODAY
#MarkMyWords #IllShowYou #WhatDoYouMean #Sorry #LoveYourself #Company #NoPressure #NoSense #TheFeeling #LifeIsWorthLiving #WhereAreUNow #Children #Purpose #BieberOnAMAs #JustinBieberBRITs #UnlimitedMoves #100MBeliebers
On February 7, 2011 Justin had a picture called 'creep' from the Super Bowl advertisement. On 27 February 2011 Justin had a picture of him playing hockey.