>> Hi.
>> It's Allen Downey.
>> [LAUGH] >> I'm Charles Severance.
>> Charles, it's great to see you.
>> We're co-authors.
>> Yes. >> We've never met in person.
We talked on the phone.
This is the famous Jeff Elkner of course.
>> I'm thrilled. Jeff, it's nice to meet you.
>> Made famous by this guy.
>> [LAUGH] Yeah, well we all, everybody got made famous.
>> That's right.
>> So the first question I was asking Jeff, and
he doesn't even know the answer to.
Is why did you choose GFDL back in 1999?
That was before creative commons, before OCW.
Before everything.
>> Yeah. >> What possessed you?
>> You know actually the first version of the book I put it under the Gnu three.
>> GFDL?
>> No, not.
>> GPL >> The GPL.
>> Oh, you did GPL?
>> Because I didn't even know about the FTL.
>> And then somebody got a hold of you from MIT.
>> And they said, wait a minute, this is documentation, this is not code.
You should have used this other license and so I switched.
And then when Creative Commons came along, some of those licenses have been useful.
>> Yep. >> Actually part of the reason that
working with O'Reilly has worked out very well.
>> Yeah. >> I do things usually under
a non commercial >> Yeah.
>> Creative Commons license.