Like no terrorist organisation before, IS has used Twitter and other social media channels to broadcast its message, inspire followers and recruit new fighters.
The findings presents an opportunity to leverage the strength of the IS opponents to counter the IS message on Twitter.
"Organisations such as the US military and the State Department looking to counter-message ISIS on Twitter should tailor messages and target them to specific communities," Elizabeth Bodine-Baron, study's lead author and an engineer at RAND Corporation, an American nonprofit research organisation, said in a statement.
The researchers used a variety of methods to analyse 23 million tweets posted by 771,327 users from July 2014 to April 2015.
The findings allowed researchers to identify more than 20,000 distinct user communities and group those into four major meta-communities that characterise the conversation about IS on Twitter.
Those four meta-communities include: Shia, Sunni, Syrian mujahedeen (opposed to the leadership of Bashar al-Assad in Syria with mixed attitudes toward ISIS) and ISIS supporters
Though fragmented, the patterns of connection between the communities opposed to ISIS suggest inroads for influence that the US government's social media strategy should explore in order to weaken the ISIS Twitter propaganda and online recruitment, according to researchers.
The researchers used different network analysis tools and algorithms to identify and characterize the conversation on Twitter about ISIS. For example, researchers found that they could separate supporters from opponents using a simple method: ISIS supporters typically refer to the organisation in Arabic as the "Islamic State," whereas opponents typically use the disrespectful Arabic acronym "Daesh."
They say the method can continue to be used to gauge the worldwide activity of supporters and opponents of ISIS.
The study showed that near the end of its reporting period (spring 2015), the number of ISIS supporters active on Twitter decreased while the number of opponents increased.
This change coincided with Twitter's campaign to suspend the accounts of IS supporters.
Researchers also found that ISIS atrocities such as the burning of the body of a Jordanian pilot sparked a huge upsurge in anti-IS tweets.
