What's difference between "have a party" and "throw a party"

"have a party" is for people who have very elegant and carefully-planned sophisticated occasions.

"throw a party" is for young people who spontaneously say to a bunch of friends: "Bring over some beer and chips and we'll party."

You don't think you can say "Martha is throwing a party in honor of George's retirement next month. Make sure you put it on your calendar now so you don't miss it."?

BarbaraPAYou don't think you can say "Martha is throwing a party in honor of George's retirement next month. Make sure you put it on your calendar now so you don't miss it."?

I could.

Then you mean both expression have the same meaning? Or any else?

Then you mean both expressions have the same meaning?
Yes, they do. The context is a little different in my opinion.