Background to the holy wars and the First Crusade's conquest of Jerusalem, a holy city for Jews, Christians and Muslims.
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Facebook CEO Mark Zuckerberg during a presentation in Menlo Park, California, USA. 4 April 2013. (PETER DaSILVA/EPA)
With almost 2,000 signatories, a new petition is calling on Mark Zuckerberg to change Facebook's censorship policies. Kurds are concerned the social media site is working with the Turkish government to target their political and cultural content.