Terrorism is one of the biggest challenges in our world. After 9/11 terrorist attack in USA, a war against terrorism was launched by many governments around the world. This war against terrorism still continues today, and this war has become more severe and deep (i.e. Syria, Philippines, Iraq and Somalia).
It is very useful to start with the definition of terrorism first. In this study, the definitions of terrorism of Walter and Sandler, CIA (Central Intelligence Agency ) and NATO (North Atlantic Treaty Organization) were used. According to Central Intelligence Agency, terrorism means premeditated, politically motivated violence perpetrated against noncombatant targets by subnational groups or clandestine agents, usually intended to influence an audience. Furthermore, NATO states that terrorism means the illegal use or attempted use of physical force, the instilling of fear and terror, against persons or properties in an attempt to coerce or manipulate regimes or communities, or to obtain control over the population, to achieve political, religious or ideological goals. Finally, Walter and Sandler describe global and domestic terrorism as planned use or threat of use of extra-normal violence or aggression to accomplish a political goal by coercion or apprehension of a targeted audience. However, despite all these definitions, terrorism is a complicated phenomenon; therefore, it cannot be explained by just one case or event. Terrorism needs to be explained more fully and in-depth. 
Some scholars stated that modern terrorism began with the French Revolution in 1789. Some other scholars such as Kaplan and Rapoport think that modern terrorism started in Russia in the end of 1880. Rapoport considers that terrorism consists of 4 main waves. Anarchist wave, anti-colonial wave, new left wave and religious wave are the 4 waves of modern terrorism. I think that current terrorism is different than four waves of terrorism. This current terrorism could be considered as a fifth wave of terrorism. Martin thinks that terrorism has been a dark character of personal behavior since the dawn of recorded history. Current terrorism varies from past acts of terrorism. Terrorism is a mobile, global threat in the modern era. Terrorist organizations or terrorists could easily create and increase fear through sophisticated communication Technologies such as social media. Terrorist organizations are now better positioned to profit from current technological developments than any other suspect. The propensity to use software makes it difficult for terrorist organizations to beat modern counter- terrorism tactics. Nevertheless, contemporary terrorist organizations vary because they do not see their organizations as strong enough to fight a real war with their own or other countries. However, the global terror and terrorist organizations that we face today are quite different from previous terrorist organizations. Alternatively, they prefer violence as the best way to fight for themselves. Although some governments have been suffering from terrorism for a long time, the 9/11 has shown that terrorism is the biggest problem in the world. This problem has grown in scope and severity over time. 
The world had faced with many terrorist organizations until 2014. However, after 2014, the world faced with the most complicated terrorist organizations such as ISIS (Islamic State of Iraq and Syria). ISIS has been running a more positive propaganda campaign, emphasizing the state-building and welfare schemes run by these organizations and these elements make ISIS more complicated. In parallel with these thoughts, Atran argues that military struggle with ISIS and other terrorist organizations is not enough. Western governments need to fight against ISIS and other extremist organizations also in psychological area. Western countries generally underestimate ISIS and this is western countries’ one of the biggest problem in the fighting against ISIS and other extremist organizations.
On June 29, 2014, ISIS officially declared the establishment of an Islamic Caliphate in Syria and Iraq. This terrorist organization has had a pervasive presence in both social media and the mainstream media. This type of terror was different than the previous examples. ISIS has been very well integrated into the new technology such as social media and smart phone and it has been using them very effectively. The most important of these new technologies used by ISIS is social media. In particular, in recent years, the development of social media and mass media has also affected terrorism. Increasing the importance of social media in recent years has benefited the terrorist organizations. Today, terrorist organizations make their propaganda through social media and mass media. There is a relationship between mass media and terrorist organizations, based on “mutual benefit”. 
This study examines the connection between social media and terrorist organizations, especially ISIS. This paper is tried to explain how ISIS uses social media, specifically twitter. In this context, the tweets of ISIS sympathizers between 2016-2017 were examined and then the sympathizers were divided into two groups based on their number of followers. Subsequently, it was investigated whether the two groups shared mainly terrorist/violent content or religious-based posts. Lastly, 20 users who posted the most tweets were found, and these users were divided into two again based on their number of followers. As in the previous stage, it was analyzed whether both groups shared terror or religious content. All analyzes in this study were made with R programming language and tweets were analyzed with dictionary-based research method.
Digital world provides freedom to exchange communication and thought flows, as there are certain organizations who misuse the power of the internet, social media and online forums to promote false views and harmful impact on others. In line with this thought, Chalothorn and Ellman also think that the internet has become an important instrument for communication, training, fundraising, media operations, and recruiting for radical and extremist organizations, especially since the early 2000s.
In the early literature, the use of web forums by terrorist organizations is frequently emphasized. Early literature emphasizes that web forums have been major areas on the internet for social networking and debate. They are also used for correspondence by some extremist organizations and for disseminating their philosophies to the public. Often, since it can be reached anywhere and provides access to a wide variety of ideological content that can be converted into different languages, the internet and web forums have become the key instrument used by terrorists.
Likewise, Rebollo et al.  think that extremist groups and terrorist organizations use social networks and the internet to spread messages with the aim of manipulating individuals and attracting new participants. Social networks play a very significant part in people’s way of thought. Repeated messaging may reinforce political ideas or even flip the way of thinking of the most indecisive when correctly aimed.
There has been a dramatic increase in the use of social media in the 2010s. With the increasing popularity of social media, it has become possible to see many posts about terrorism and hate crimes on social media. In parallel with this, in recent years, the relationship between social media and terrorist organizations, especially in the context of ISIS, has been studied extensively.
Some of the most important examples of the relationship between social media terrorism is Al-Shabaab broadcasted live on twitter its armed attack to a shopping mall.  Similarly, ISIS broadcasted live on internet the killing of Turkish and Jordanian soldiers. Terrorist organizations aim to expand their wars with these strategies. At the same time, social media is used to create fear in the public. Likewise, some scholar such as Sharif, Mumtaz, Shafiq, Riaz and Choi think that in order to promote negative ideologies by sharing radical content among audiences, many people use social media sites. Waqas Sharif, Shahzad Mumtaz, Zubair Shafiq, Omer Riaz, Tenvir Ali, Gyu Sang Choi and Mujtaba Husnain argue that many terrorist organizations such as ISIS effectively use social media today. They support that aggressive and offensive tweets, posts, comments, and hateful statements based on agendas are circulated by these extremist groups. More than 100,000 tweets were posted during the ISIS invasion of Iraq and photographs were posted on internet from the captured cities. Tweets created a fear over many city residents in Iraq and Syria and people began to flee from their cities. Similarly, Weinburg and Eubank think that modern forms of communication, social media, promote the spread of terrorism from one place to another.
On the other hand, terrorist organizations gain many supporters through their propaganda in social media. Sharif, Mumtaz, Shafiq, Riaz and Choi support that by reaching a worldwide audience, social media has now become the best way for these radical groups and terrorist organizations to attract new people into their organizations, and then these groups eventually begin to influence newly recruited people to promote aggression and extremism. For this reason, terrorist organizations like ISIS organize their propaganda on social media in many different languages. People who decide to join organizations communicate with members of the organization through social media such as Facebook.
Almost 5000 European young people joined ISIS. This number is really high compare to 1980 Afghanistan-USSR war mujahedin population and 2003 USA Iraq invasion. This is because new ISIS terrorism offers freedom to Muslim European in the world and afterlife. Also, social change and media in Europe play an important role in member acquisition. Most of the young people are afraid of being unemployment, homeless and etc… But ISIS offers to be hero and martyr, also in ISIS people doesn’t need to be afraid about job and home. Other important thing in the rising of ISIS is identity crisis in Europe. For a long time, most of the European people were not seen Muslim European people as their country citizen. For this reason, ISIS offers a good alternative to these young people. ISIS offers them to be citizen of the caliphate and these young people come to Syria to support ISIS and this caliphate. Such propaganda of ISIS reaches millions of young people through social media. The author thinks that social media plays an important role in the recruitment process. 
Similarly, a research released by the USA Center for Cyber and Homeland Security on terrorism explains that social media is a central instrument for encouraging radicalization, and the research further shows that this is a commonly adopted method of attracting new recruits of terrorist organizations around the world, concentrating of particular on users from Europe and the United States. The pervasive use of social media has affected the lives of individuals in societies. Extremist groups today also use social media to distribute their opinions to a wider audience, either to create support for their cause or to attract individuals. [33, 34]
In parallel with these studies, Ferrara thinks that terrorist acts carried out on behalf of ISIS between 2014 and 2018 by lone wolf terrorists or sleeper cells on American and European soil inform everyone of the value of recognizing the mechanisms of radicalization mediated by networks of social media contact. Many countries and non-governmental organizations have been involved in the dissemination of their propaganda on social media. In some cases, these networks have reportedly been polluted with content to manipulate public opinion, [36, 37] or to obstruct the capacity of social movements to connect, organize and mobilize. On the other hand, through hatred and inflammatory tweets, posts or speeches, and even slick videos that contribute to the spread of violence and radicalization, the growth of social media has led to a growing online cyber-war.
Social media platforms such as twitter and YouTube have become the platforms actively used by many terrorist organizations, especially ISIS. Some scholars in the literature focus on YouTube strategies of ISIS and other organizations. One of these studies was written by Derek O’Callaghan, Nico Prucha, Derek Greene, Maura Conway, Joe Carthy, and P’adraig Cunningham. According to them, a number of suspected sources utilize YouTube to record and showcase actions as they unfold, where, according to official estimates, over a million videos have been posted since January 2012, which in turn have earned hundreds of millions of views. These data only cover the period from the Syrian civil war involving terrorism to 2014.
The bulk of these are militant jihadists, with a specific preference for the doctrine of ISIS reflected in their orientation. Founded in the summer of 2013, the top rated YouTube channel has over 6,500 subscribers and 1.7 million cumulative views of 1,000 + episodes, most of which show the everyday situation on the ground in the mainly Sunni sectors under attack in Aleppo. 
Similarly, Kohlmann and Alkhouri suggest that as a recruiting instrument, ISIS also produces high quality videos in many languages. As an example, ISIS produced an English video entitled “There is No Life Without Jihad” featuring Foreign fighters who have to join others. Most of ISIS’ propaganda focuses on reports on military victories and the progress of ISIS in enforcing various facets of Islamic law or order. Likewise, in most cases, people entering ISIS received information from the internet that came from notable people in the form of tweets, personal communication via social media, and videos and teachings digitally.
Some scholars in the literature have focused on ISIS’ usage of Twitter. A research reported in reveals that more than 125,000 Twitter accounts were identified in 2015 through human judgments linked to terrorist and extremist actions.  While there is sparse specific literature on the use of social media by ISIS, there are clear signs that the party tends to be reasonably media savvy with a strong presence on multiple social media sites.  ISIS, for instance, maintains several Twitter accounts that spread the message of the community in many languages. New ones are quickly created to replace them when accounts are taken down.
Similar research by Berger and Morgan  indicated that much of the popularity of ISIS on Twitter is responsible for a small number of highly-effective accounts (500-1000 users). Berger’s following study, however, indicated that the reach of ISIS has been stalled for months since the start of 2016, owing to Twitter’s increasingly stringent account suspension policies. Most accounts have a small number of followers, but a substantial number of ISIS supporters have managed to get a large number of followers before being removed. On Twitter, a large proportion of ISIS supporters’ accounts have been very involved in activity. Berger and Morgan have also seen a substantial uptake in the number of adoptions in the three months between March and June 2015, peaking at nearly 1,000 adoptions per day. At least 10,000 tweets a day (70,000-100,000 tweets / week) were produced from ISIS supporter’s accounts during that time.
It is generally claimed that by streaming its savage attacks over social media outlets such as Twitter, which helps radicalize and eventually attract fighters from across the world, ISIS control to expand its membership to tens of thousands of people .
Walid Magdy, Kareem Darwish, and Ingmar Weber propose an analysis using data from Twitter to help grasp the origins of this organization and its backers. Walid Magdy, Kareem Darwish, and Ingmar Weber begin by compiling and classifying vast quantities of ISIS-related Arabic tweets into pro-ISIS and anti-ISIS.
In this study, an analysis based on dictionary-based method is used and the tweets of ISIS sympathizers between 2016 and 2017 were analyzed within the scope of the content. Within the scope of the Twitter analysis, 20000 tweets sent by ISIS sympathizers between 2016 and 2017 were examined. The tweets sent by the sympathizers were analyzed by dictionary-based analysis method.
I use dictionary-based research to automatically identify terrorism/violent and religious rhetoric in the tweets despite the complexity of manually coding over 20000 long texts. As a classical content analysis is a very time-consuming and potentially costly endeavor, I have also established a much simpler accessible terrorism and religious metric focused on computer-driven content analysis.
This metric is based on the dictionary method where a program calculates the proportion of terms that I find to be terrorism/violent or religious markers. This indicates that terms are the standard of measurement, instead of paragraphs. The choice of terms for the dictionary from this analysis was based on both analytical and theoretical logic. For motivation, I used analytical samples to draw up a collection of terms used by some newspapers to describe their skepticism or positivity against ties between the terrorism/violent and religious.
This method scans the records for a specified set of words to occur and gives each record a prevalence score for each word. This helps one to analyze terrorism and religious counts and proportions by interest factors, including years, and months. I create the dictionary of terror and religious words, then reading a random subset of tweets and defining possibly applicable words, then running the study centered on those terms, and eventually discovering additional terms in documents defined by the algorithm as terrorism content or religious content.
In the Twitter analysis, firstly, 20000 tweets were divided into users with high followers and fewer followers, and it was analyzed whether the tweets sent by both groups were related with religious or terrorism. In this analysis, those with less than 4000 followers are included in the category of those with fewer followers, and those with more than 4000 followers are included in the category with many followers. Later, those who tweeted the most on the subject were found, and the ones who tweeted the most were divided into two categories according to the number of followers, and it was examined whether each category tweeted based on religion or terrorism.
20000 tweets sent by ISIS sympathizers between 2016-2017 were analyzed. In this analysis, firstly all of the tweets sent were examined. Looking at the general results, it is revealed that most of the tweets contain terrorism and violence.
Figure 1- General Tweet Analysis results
In the next stage, all of the tweets are divided into two groups based on their number of followers. First, the tweets of users with more than 4000 followers were examined. It has been found that users with a high number of followers predominantly posted terror and violent content tweets.
Figure 2- Results of users with more than 4000
Later, the tweets posted by users with less than 4000 followers were analyzed and it was observed that, unlike those with a high number of followers, more religious tweets were posted. However, it has been observed that the rates of religious tweets and terror content tweets are very close to each other.
Figure 3- Users with Less than 4000 Followers Results
In the second step, the tweets of 20 users who posted the most tweets were examined.
Figure 4- 10 Users who Posted the Most Tweets
As a result of this analysis, it was found that the 20 users who tweeted the most often posted terror content tweets.
Figure 5- Results of 20 Users who Tweeted the Most Often
Users who most tweeted are divided into two groups based on their number of followers among themselves. Unlike the general tweet analysis, both groups predominantly posted terrorism content. However, it was found that users with fewer followers had more religious tweets than those with more users.
Most tweeted users with fewer followers
Most tweeted users with many followers
Figure 6 – Results of 20 Users who Tweeted the Most Often
Terrorism is one of the biggest problems facing the world in recent years. Terrorism has become more complicated, especially with the advancement of technology and the spread of social media. Because social media offers the opportunity to transfer the propaganda and messages of terrorist organizations to millions of people in a very short time.
ISIS has observed these opportunities offered by social media well and used advancing technologies and social media very effectively. One of the social media platforms that ISIS uses most effectively is Twitter. In this context, how and for what purpose ISIS sympathizers use Twitter was examined in this study. The study includes 20000 tweets of ISIS sympathizers between 2016 and 2017.
Many important findings have been reached in this study. The first finding emerged from the general analysis of tweets. The overall analysis of the tweets was found to be involved terror and violence content as expected. However, the most important findings are the results obtained as a result of dividing ISIS sympathizers into groups based on their number of followers.
As a result of this grouping, it was found that users with more followers tweeted terrorist and violent content. However, it was found that users with few followers mainly tweet religious content. These two findings are in parallel with ISIS’s use of twitter. The reason why ISIS uses social media and Twitter is to spread fear all over the world, to recruit new member and to justify their actions and attacks. From this point of view, the strategy of spreading fear to the whole world is managed by users with many followers. Because thousands of people see the tweets of these users in a very short time and the effect of these tweets are more. Especially with Twitter’s features such as retweet, this number reaches millions in a very short time.
On the other hand, users with fewer followers are generally followed by people with whom they share similar views. For this reason, these users are not on a mission to spread fear and therefore do not need to tweet related with terror and violent content. However, the function of these users with few followers is to interpret ISIS’ actions on a religious level among people who share similar views and thus legitimize the actions. In this way, it is aimed to continue the support of the sympathizers to ISIS and to justify the activities of the organization by interpreting them on a religious level. These results are also supported by the analysis findings of the tweets of the users who tweet the most.
This study is quite different from the literature in terms of the results achieved. There are some researches on the use of Twitter by ISIS in the early literature, but there is no user-based study. In addition, the dictionary-based method approach used in the study is not a frequently used method in the literature and this research differs in terms of research method.
The study has some limitations. One of the primary limitations of the study is that the tweets only cover the years 2016 and 2017. Future studies that cover a wider time period can reach more generalizable results.