Explainer: The Iron Dome, Israel's key anti-missile shield

Israel's air defences were in operation on Saturday night, after Iran launched more than 300 drones and missiles in an unprecedented direct attack. That starts with the Iron Dome, which has intercepted thousands of rockets since it first went into operation in 2011, provides Israel with crucial cover during times of conflict. It has been heavily relied upon to protect military and civilian sites from frequent barrages of rockets fired from Gaza and Lebanon in the ongoing war between Israel and Hamas.