It is widely reported Iran today launched a substantial number (some say 100s) of cruise missiles at targets in Israel. It is also suggested most of these were intercepted and destroyed without reaching their targets.
I presume Israel will return the favor and launch at targets in Iran. They will very likely have greater success although that is not certain.
Iran seemingly did not launch harder-to-intercept ballistic missiles at Israel. Ballistic missiles tend to be substantially more expensive than cruise missiles.
Cruise missiles are small, unmanned aircraft that take off and fly to their targets, carrying explosives. Ballistic missiles follow paths similar to high-arcing howitzer shells, and also carry explosives. Cruise missiles can loiter while a target is located, ballistic missiles cannot.
The US has announced it will assist Israel's defense. What happens next is unclear, maybe Iran's attack is a symbolic one-off, maybe it's the beginning of a wider regional war.
Later … More recent reports claim ballistic missiles were also used, and make a distinction between suicide drones and cruise missiles, both of which were apparently flown. One supposes the cruise missiles fly faster than the suicide drones and lack the ability to loiter.
Apparently Iran has called their salvo a “one-off” response to the attack near their consulate in Damascus, meaning that it can, if Israel chooses, end here or it can go further. Biden, of course, is pushing for “end here.”
