Attacks on Westminster, Manchester Arena, and London Bridge by radicalised Islamist extremists - as well as further afield in Brussels, Nice, Paris - have cast the issue of Islamist terrorism into sharp relief.
But you'd be surprised at the true meanings of some of the words extremists used to justify atrocities, like fatwa, caliphate... even jihad.
Farooq Aftab and Ibrahim Ikhlaf from the Ahmadiyya Muslim Association UK, appeared on The Week with Jonny Gould for a deep discussion on the religion of Islam, and how it can't be associated with terrorist acts.
They said: "The role of the caliph is essentially two things. One, bring people towards their creator. Secondly, to serve humanity.
“There’s no political aspirations to [the word] 'caliphate'. It’s purely religious and it leads people to do good in their society.
"Fatwa is an edict while jihad means struggle, but in 140 chapters in the holy Quran, whenever god speaks about a battle or fighting, Jihad has not been used in that context.
"Jihad means clearly a struggle to please God, and the highest level of jihad means fighting yourself and your ego. That is what it means."
Listen to the interview above.