In my home country---the land far and away---a car/vehicle blasting its horn at you means you are possibly going to die., i.e., someone is going to hit you/run over you if you don't move/react the right way.
In Oman, it means many, many, less important things.
It means, "hey Mohammed, come take my order!" (from Mr. Lazy-Ass who can't get out of his car at the restaurant/coffeeshop).
It means, "hey there, lsmat, ya ukti," (from, 'I am a creepy dude in a car trying to hit on you')... to anything female that moves."
It means, "pull over, because you are going the speed limit," from (I want to kill myself and/or innocent others" on the expressway guy)... who ends up right beside you at the next red light, but whatev...
It means, "your abaya is sticking out the door!" from (possibly concerned---but more than likely, try-to flirt-with-you guys).
It also means, "thank you" which always, always, scares the crap out of me, when we let someone go into our lane when it is polite to help others merge in traffic.
I don't know, I'll never get used to Oman's use of hazard lights and the car horn, I think. I will always, always, think I am about to possibly die, when I hear a horn blast.
And then, when I don't die, I will be so irate, when I see some lazy-ass in his car with ac on, while some Indian dude has to come out the ac coffeeshop in the middle of the afternoon, to go make change, and deliver a ten second chai karak.