There are some terrorist groups such as ISIS in the Islamic world, backed by the non-Islamic western states, claim that they are representing Islam and also they are trying to establish Islamic caliphate or state. But, unfortunately they misuse the name of Islamic state to deceive the young Muslim generation. If we study their beliefs and practices we find out that ISIS has nothing to do with Islam.
The holy Quran as the main source of Islamic teachings, for all the different Islamic sects, prohibits the extremism exhibited by ISIS introducing moderation as the essential part of the faith. The holy Quran states clearly: “We made you to be a community of the middle way, so that (with the example of your lives) you might bear witness to the truth before all mankind.”  What Quran means by the middle way is totally opposed to the extremism and terrorism.
One of the very foundational principle of Islam is justice and the holy Quran tells the believers that “O you who believe! Stand out firmly for justice, as witnesses to God, even against yourselves, or your parents, or your kin, and whether it be (against) rich or poor: for God can best protect both.”  But these pseudo Islamic groups such as ISIS do not observe this essential Islamic rule; because, they have massacred thousands of innocent Muslim and non-Muslim civilians in Iraq, Syria and Afghanistan for the past few years.
They call themselves Mujahidin while jihad, literally, means to struggle, strive and exert effort. Of course Islam did allow legitimate self-defense, but it also prohibits the killing of non-combatants, even in times of war or conflict. According to the Holy Quran aggression is never permitted. “And fight in the cause of God those who fight against you, and do not commit aggression. Indeed God does not love those who are aggressors,” 
Extremist and terrorist groups like ISIS who commit crimes, against innocent Muslims, should not be called Islamic State or Mujahidin; rather, the ISIS should be called criminals. Because their social and political conduct is categorically opposed to Quranic and Islamic teachings as some of them were mentioned briefly in this article.
 Chapter 2, verse 143. وَكَذَلِكَ جَعَلْنَاكُمْ أُمَّةً وَسَطًا لِّتَكُونُواْ شُهَدَاء عَلَى النَّاسِ وَیَكُونَ الرَّسُولُ عَلَیْكُمْ شَهِیدًا
 Chapter 4, verse 135. یَا أَیُّهَا الَّذِینَ آمَنُواْ كُونُواْ قَوَّامِینَ بِالْقِسْطِ شُهَدَاء لِلّهِ وَلَوْ عَلَى أَنفُسِكُمْ أَوِ الْوَالِدَیْنِ وَالأَقْرَبِینَ إِن یَكُنْ غَنِیًّا أَوْ فَقَیرًا فَاللّهُ أَوْلَى بِهِمَا فَلاَ تَتَّبِعُواْ الْهَوَى أَن تَعْدِلُواْ وَإِن تَلْوُواْ أَوْ تُعْرِضُواْ فَإِنَّ اللّهَ كَانَ بِمَا تَعْمَلُونَ خَبِیرًا Chapter 2, verse 190. وَقَاتِلُواْ فِی سَبِیلِ اللّهِ الَّذِینَ یُقَاتِلُونَكُمْ وَلاَ تَعْتَدُواْ إِنَّ اللّهَ لاَ یُحِبُّ الْمُعْتَدِینَ