Well folks, we’ve had a couple of whistle challenges here lately,-and here’s a new one:
What exactly is it that makes a recorder different from a whistle?
I’m not talking about sound here, but more about physical appearance.
Depending on the replies I will make a few comments later,- but first;-have a go at it folks . . . . .
So, what makes a recorder different from a whistle?
The primary difference is in the head. No, not the head of the recorder or whistle, the head of the one blowing the hot air into it. More of an attitude towards life thing. 
Really, no offense is meant but this topic really calls out for all the latent &^%@#$ jokes out there. Truth be know I am a recovering recorder player myself. I’ve been clean for 15 years now.
The serious answer depends on what era recorder you are talking about. Early block flutes were much like today’s whistles. The recorder has gone through hundreds of years of evolution to get to where we know it today. And yet, the recorders representing different historical eras are still made and played.
Feadoggie
Whistles are prettier 
Well, a recorder has a thumb hole and pinky C (that, I think, has two holes in it). And, usually they’re curvier.
The primary difference is in the head. No, not the head of the recorder or whistle, the head of the one blowing the hot air into it
Excellent,-spot on 
Keep it coming folks.
If you’re just asking about physical appearance, it is simply that a rec***er has 7 fingerholes and a thumbhole, whereas a whistle of the traditional sort has only six fingerholes and no thumbhole.
There are certain schools of design… whistles more commonly being of metal, and recorders being more commonly turned from wood (or, historically of ivory or bone). Some whistles look more like some recorders than like a Clarke tinwhistle, but if they have six fingerholes, tuned diatonically, beginning at do, we call them whistles.
Recorders have record buttons and backlit displays, whistles do not.
Cheap plastic see-through colored recorders are always for sale at Dollar Stores. Whistles, they don’t even sell these in most music stores.
Our county recorder has very little musical ability and if you place a thumb on her backside she’ll slap you one.
There are some whistlers that have not seen a recorder. I had one with reel to reel tape that would record for many hours. I think what is used now are some kind of pod or mp3?
Doggone it, you guys already took all the good jokes before I got here. 
Tom
Recorders/recorder players are all Petrified. Whistles rock.
Whistles don’t look like recorders except for those whistles which do.
Whistles don’t sound like recorders except for those whistles which do.
Whistles aren’t made of wood like recorders, except for those whistles which are.
Whistle players don’t play anything except ITM except for those whistle players who do.
Whistle players don’t play recorders except for those whistle players who do.
Now, that is response worthy of some kind of award, IMHO.
To which I can only add, because I fall into the group described by the last line quoted:
Recorders don’t sound like whistles except for those recorders which do. 
Yeah walrii gets my vote for the best response of the month!
Yeah walrii gets my vote for the best response of the month!
I’ll second that one
That looks like the best here also. The only one I could add is perhaps.
Whistle players that don’t know the difference may not have a whistle yet, except for those that do.