Renaming a "message"?

How can I rename a “message”?
Also can I give a “list” a name?

To give a list a name, store it in a variable.

I don't understand. Just choose "new" from the pulldown menu and make a new name.

Oh, if you want a way to have all the WHEN I RECEIVE blocks automatically change too, no, I'm afraid you can't do that.

But when I make a new “message” the old one is still there…
how do I delete the old miss named message?

If you get rid of all of the blocks which use that message name then it should be deleted.

Why would you want to rename a broadcast? you can use lambda narrow casts!

While you can certainly reimplement broadcasts using anonymous procedures, I think that's overcomplicating things a bit.

And sometimes it's useful to send a message to all sprites

If you remove from the scripting area all the blocks that use the old name, then the name itself will disappear from the menu of new BROADCAST and WHEN I RECEIVE blocks that you add to the scripting area (or a Block Editor). Existing blocks in the scripting area are not changed.