AL QAEDA IN THE ARABIAN PENINSULA (AQAP)

Al Qaeda in the Arabian Peninsula (AQAP), which U.S. President Barack Obama has described as "al Qaeda's most active operational affiliate," was founded in January 2009 when al Qaeda's Saudi and Yemeni branches merged. The Islamic militant group is headquartered in Yemen and has conducted many of its attacks on Yemeni soil, primarily in the south, but has also proved to have a global reach. Yemeni-American cleric Anwar al-Awlaki, who was killed in a U.S. drone strike in Yemen last September, was one of the group's primary propagandists, playing a role in the radicalization of an astonishing array of terrorists. AQAP-linked figures who have surfaced in the United States include the Fort Hood shooter Nidal Malik Hasan, the "underwear bomber" Umar Farouk Abdulmutallab, and the Times Square plotter Faisal Shahzad.

As the Yemeni state crumbles, al Qaeda has made impressive gains, even establishing an "Islamic emirate" in the southern province of Abyan. AQAP leader Nasir al-Wuhayshi once served as Osama bin Laden's personal secretary and has several times been rumored dead, only to pop up again. The Washington Post has reported that the United States is establishing "secret drone bases" in the region as part of an effort to eliminate high-ranking AQAP officials in Yemen and is seeking to expand the campaign by launching strikes against suspected terrorists even when the identities of those who could be killed are unknown.

Above, two suspected members of al Qaeda in Yemen, accused of plotting attacks on Western targets in the country, are seen behind bars in Sanaa, the Yemeni capital, in February 2006.

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BOKO HARAM

The radical Islamist cleric Mohammed Yusuf founded Boko Haram -- which roughly translates to "Western education is a sin" -- in 2002 with the goal of establishing an Islamic state in Nigeria. From its base in the country's north, the group has been carrying out attacks against Nigerian civilians, police, and politicians since 2009 -- the same year that Yusuf died in police custody. In 2011 alone, the group bombed the U.N. headquarters and police headquarters in Abuja, while also carrying out coordinated attacks to mark President Goodluck Jonathan's inauguration and Christmas Day. Boko Haram has killed roughly 1,000 people since 2009.

The United States has accused Boko Haram of having ties with al Qaeda in the Islamic Maghreb and Somalia's al-Shabab. As Gen. Carter Ham, the head of U.S. military operations in Africa, noted in April 2011, "What is most worrying at present is … a clearly stated intent by Boko Haram and by al Qaeda in the Islamic Maghreb to coordinate and synchronize their efforts." This February, London's Daily Telegraph pointed out that the group's attacks in the Nigerian city of Kano recalled al Qaeda's operational techniques, featuring "a mixture of suicide bombers and gunmen, some in police or army uniform, [carrying] out multiple, carefully coordinated attacks on hard targets."

Above, men inspect a wrecked car after the Christmas Day bombing of a Catholic church outside Abuja by Boko Haram in 2011.

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AL-SHABAB

Originally the militant wing of the Islamic Courts Union, which assumed control over much of southern Somalia in 2006, al-Shabab initially worked to repel Ethiopia's invasion of the country in December of that year. But it has increasingly embraced transnational terrorism, orchestrating twin bombings during the World Cup in Uganda in July 2010 that killed more than 70 people. The U.S. State Department placed al-Shabab on its list of foreign terrorist organizations in February 2008 for its possible links with al Qaeda, and al Qaeda leader Ayman al-Zawahiri made the marriage official this February by announcing that al-Shabab had pledged allegiance to al Qaeda "Central."

Al-Shabab has risen to become one of the most feared groups in war-torn Somalia, though it has faced setbacks in the past year: Last August, it was forced from the capital, Mogadishu, by international and Somali government forces. The Islamist group, which still controls parts of southern Somalia and claims to have several thousand fighters under its wing, grabbed headlines in recent months for obstructing humanitarian aid during Somalia's famine, launching brazen attacks in Mogadishu, and battling Ethiopian, Kenyan, and Somali troops throughout the country.

Above, Somali women carry weapons during a demonstration organized by al-Shabab in July 2010.

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AL QAEDA IN THE ISLAMIC MAGHREB

Al Qaeda in the Islamic Maghreb (AQIM) was founded as an Islamist resistance movement to the Algerian government in 1992, when Algeria's military rulers halted parliamentary elections to prevent a coalition of Islamist militants and moderates from winning power. Initially called the Salafist Group for Preaching and Combat, the group changed its name and merged with al Qaeda in 2006. Even before then, AQIM had received funding from bin Laden and expressed support for al Qaeda's jihad against the United States.

Now predominantly self-funded through a mixture of arms and drug trafficking and kidnappings for ransom, the group has set its sights beyond North Africa -- to Iraq and Western Europe, among other places. But AQIM hasn't forgotten the home front: The group continues to carry out attacks in Algeria, including the 2007 bombing of the U.N. headquarters in Algiers. "Our general goals are the same goals of al Qaeda the mother," AQIM leader Abdelmalek Droukdel told the New York Times in 2008. More recently, AQIM has taken Italian, French, and German hostages, amid concerns in the West that the group is exploiting the seizure of northern Mali by Tuareg rebels to expand its reach.

Above, a picture posted by AQIM in April 2007 on alhesbah.org shows one of the suicide bombers who took part in attacks in the Algerian capital, which hit the prime minister's office and killed more than 20 people.

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JEMAAH ISLAMIYAH

Jemaah Islamiyah (JI) was founded in the late 1980s and has a strong militant presence in many Southeast Asian countries. JI has pursued its goal of establishing an Islamic state by attacking or plotting against U.S. and Western targets in Indonesia (the world's most populous Muslim country), Singapore, and the Philippines. Initially, the militants mostly abstained from violence. But JI shifted tactics in the late 1990s -- around the same time it is suspected to have first established contact with al Qaeda in Afghanistan -- launching attacks against both government and civilian targets.

Some of the most notorious assaults linked to the group include an assassination attempt against the Filipino ambassador to Indonesia in August 2000, a wave of church bombings in 38 locations in Indonesia on Christmas Eve in 2000, and a series of bombings around the subway in Manila, Philippines, in December 2000. In October 2002, JI orchestrated Indonesia's deadliest terrorist attack, detonating three bombs simultaneously in a nightclub district on the island of Bali that killed more than 200 people, many of them foreign tourists. These attacks -- and the group's suspected ties to bin Laden -- earned JI a spot on the United States' list of foreign terrorist organizations. Three years later, the organization carried out another string of deadly suicide bombings in Bali. A JI splinter group headed by Noordin Mohammad Top was suspected of orchestrating suicide bombings at luxury hotels in Jakarta, the Indonesian capital, in July 2009, but Southeast Asian governments have recently arrested or taken out several leaders of JI and its offshoots, including Noordin, who was killed by Indonesian police in 2009. 

Above, Abu Bakar Bashir, JI's alleged spiritual leader, smiles while arriving in court for a trial in Jakarta in May 2003. He was convicted of inciting terrorism in June 2011.

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Abu Sayyaf

Abu Sayyaf, which was formed in the early 1990s and has boasted of its ties to al Qaeda, strives to create an independent Islamic state in the southern Philippines. The militant group carried out its first large-scale attack in April 1995, when gunmen attacked a Christian town in the southern region of Mindanao, killing 53 people. (The group reportedly plotted an assassination attempt against Pope John Paul II as well when he visited the country that year.)

When the organization's leader, Abdurajak Janjalani, was killed in a confrontation with the Philippine Army in 1998, his brother Khadaffy assumed control and shifted the group's focus from kidnapping people for ransom to urban bombings. Abu Sayyaf perpetrated the worst terrorist attack in Philippine history in February 2004, when it bombed a ferry in Manila Bay, killing 116 people. More recently, it was accused of plotting to assassinate then-President Gloria Arroyo in February 2008. Although the group's membership has fallen from the thousands to the hundreds in recent years, it still maintains ties with groups such as Jemaah Islamiyah.

Above, Abu Sayyaf gunmen guard a mosque in May 2000 on impoverished Jolo Island, where Abu Sayyaf leaders and a group of negotiators met to release 21 Asian and Western hostages.

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LASHKAR-E-TAIBA

Lashkar-e-Taiba (LeT) also known as the Army of the Righteous, is one of the largest militant Islamist groups in South Asia, with a membership roster estimated to number in the thousands. Founded in the 1990s, LeT began as the military wing of Markaz-ud-Dawa-wal-Irshad, a Pakistani-based Islamist organization that opposed the Soviet presence in Afghanistan. Its immediate goal is the abolition of Indian rule in Kashmir and its incorporation into Pakistan, but it has also set its sights higher, on the destruction of India and the establishment of an Islamic state in South Asia.

Since 1993, LeT has targeted Indian troops and civilians in the disputed state of Jammu and Kashmir. More recently, however, it has taken its war into the heart of India: The group's devastating strikes inside India include an assault on the Indian Parliament in New Delhi in December 2001, the bombing of commuter trains in Mumbai in July 2006, and coordinated attacks in Mumbai in November 2008. In 2002, the Pakistani government froze LeT's assets and banned it outright after capturing senior al Qaeda official Abu Zubaydah at an LeT-affiliated safe house. In 2008, the U.S. Treasury Department imposed sanctions on four senior LeT leaders.

Above, Hafiz Saeed, LeT's founder, gestures as he leaves a news conference in Rawalpindi in April 2012 after learning that the United States had placed a $10 million bounty on his head.

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