Key Difference: ISIS stands for the Islamic State of Iraq and Syria or Islamic State of Iraq and al-Sham. The UN has accused ISIS of human rights abuses and war crimes.  In the western world, ISIS is primarily known for a series of videos showing beheadings of soldiers, civilians, journalists, and aid workers. The Taliban, also spelt as Taleban, is an Islamic fundamentalist political movement in Afghanistan. The Taliban have been accused of using terrorism as a specific tactic to further their ideological and political goals.

Terrorist groups have always existed. However, in the past couple of decades, terrorism has been on the rise. This is due to the rise of militant groups such as ISIS, Al Qaeda, Taliban, etc.
ISIS stands for the Islamic State of Iraq and Syria or Islamic State of Iraq and al-Sham. The group is also commonly known as Islamic State of Iraq and the Levant (ISIL). The group's Arabic name is transliterated as ad-Dawlah al-Islāmīyah fī al-‘Irāq wash-Shām leading to the Arabic acronym Da‘ish or DAESH.

In June 2014, ISIS officially changed its name to Islamic State (IS). However, this name has been widely criticized and condemned. In fact, UN, various other governments, and mainstream Muslim groups have refused to use it.

ISIS started out as Jama'at al-Tawhid wal-Jihad in 1999. It then changed its name to Tanzim Qaidat al-Jihad fi Bilad al-Rafidayn—commonly known as al-Qaeda in Iraq (AQI). It pledged allegiance to al-Qaeda in 2004. However, after an eight-month power struggle, Al-Qaeda cut all ties with ISIL in February 2014 citing its failure to consult and "notorious intransigence".

The UN has accused ISIS of human rights abuses and war crimes. Amnesty International has reported ethnic cleansing by the group on a "historic scale".  In the western world, ISIS is primarily known for a series of videos showing beheadings of soldiers, civilians, journalists, and aid workers. Today, ISIS controls territory in Syria and Iraq, and has additional territories in eastern Libya, the Sinai Peninsula of Egypt, and other areas of the Middle East, North Africa, South Asia, and Southeast Asia.

ISIS aims to establish an Islamic caliphate. A caliphate is an Islamic state under the rule of a caliph, i.e. a person accepted to be a political and religious successor to the prophet Muhammad. As caliphate, it claims religious, political and military authority over all Muslims worldwide.

The Taliban, also spelt as Taleban, is an Islamic fundamentalist political movement in Afghanistan. It started out as a militia group that formed in 1994 to fight against the Soviets in the Soviet war in Afghanistan. After the Soviets were defeated with the help of the Pakistanis, United States and Saudi Arabia, the Taliban formed a government claiming most of Afghanistan.

 As a government, the Taliban put in place the most extreme type of Islamic law ever seen in the Muslim world. It implemented an extreme version of Sharia law that violated basic human rights. Things were especially bad for women. Many criminals were put to death fast and without a fair court hearing. Anyone who refused to follow the law was considered a non-Muslim enemy. During this time, it is alleged that the Pakistani Inter-Services Intelligence and military provided support to the Taliban.

Eventually, the Taliban was removed from power, mainly as part of the United States War on Terror after the 9/11 attacks. After it was overthrown, Taliban reformed as an insurgency movement to fight the American-backed Karzai administration and the NATO-led International Security Assistance Force (ISAF).

Overall, the Taliban have been accused of using terrorism as a specific tactic to further their ideological and political goals. According to the United Nations, the Taliban and their allies were responsible for 75% of Afghan civilian casualties in 2010, 80% in 2011, and 80% in 2012.

Comparison between ISIS and Taliban:

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