Children and students live in this era:
- They can send each other emails, it is possible to send eamils to a list 
- They can send each other SMS, it is possible to send an sms to a group
- They can chat in a chatbox, private or in a group


> -----Original Message-----
> From: Ken Kahn [mailto:kenkahn at toontalk.com]
> Sent: dinsdag 30 oktober 2001 20:33
> To: squeak-dev at lists.squeakfoundation.org
> Subject: Re: Lots of concurrency
> 
> 
> Richard A. O'Keefe wrote:
> 
> >
> > The question I think is interesting is whether telling students to
> > think in terms of objects TALKING to each other makes it harder for
> > them to think of concurrent implementations.  Would some other
> > metaphor (perhaps sending couriers with messages, or thinking about
> > a factory with things concurrently moving from machine to machine
> > at the same time) make it easier for them to think of and understand
> > concurrency?
> >
> 
> Before settling upon a carrier pidgeon metaphor for 
> communcation in ToonTalk
> I considered lots of other alternatives including a postal 
> system with mail
> carriers and mail boxes, rivers where you can place floating 
> messages to
> those downstream, wires, fax machines, email, and telephones. I never
> considered face-to-face talking since I took for granted that 
> objects are
> spread out spatially. I think the answer to Richard's 
> question is that the
> right choice of metaphor can significantly facilitate thinking and
> understanding concurrent programs.
> 
> Wires may be how messages are really passed within and 
> between computers but
> wires are not an ideal metaphor. The messages are invisible. 
> Wires cannot be
> sent along wires. Directionality isn't apparent. Wireless 
> communication is
> even worse.
> 
> Talking or telephones aren't good because both parties need 
> to be available
> at the same time. Many-to-1 communication by telephone is 
> confusing. While
> phone numbers can be communicated over the phone that would 
> lead to a model
> where numbers denote objects or communication channels. So 
> can they be made
> up and dialed at random? Not good.
> 
> Even the postal system doesn't provide an ideal metaphor. If 
> you want to
> send the receiving end of a communication channel to someone 
> do you have to
> pick up your mail box and send it by mail to someone? And 
> then does the
> postal system know that the mailbox has moved or do you need 
> to think about
> forwarding addresses?
> 
> A bird that when given something flies to her nest and leaves 
> it there and
> returns works out very well. You can give a bird a box that 
> might contain
> other birds and nests - not too strange. The only strange 
> thing is that a
> bird always finds her nest no matter where it has been moved 
> to. But that
> doesn't seem to cause any confusion.
> 
> > All I know about Ken Kahn's ToonTalk is what I've read in 
> this thread,
> > but it sounds as though uses a "physical" rather than "verbal"
> > metaphor, so I think his observations are particularly 
> interesting here.
> >
> 
> You all are welcome to try out ToonTalk. There is a free 
> trial version and
> you are all welcome to try to beta version as well. It only 
> runs on PC with
> Windows (or Macs emulating a PC with Windows - don't know about Linux
> emulators). Details at www.toontalk.com
> 
> Best,
> 
> -ken kahn
> 
> 
> 
>