By John Gruber
Square Reader SDK lets you use Square hardware to take payments in your app.
The other big change with Markdown 1.0.1 is related to licensing. Markdown 1.0 and earlier were released under the GPL; starting with version 1.0.1, Markdown is now licensed under a less-restrictive BSD-style license.
If you’re just someone who uses Markdown, this licensing change makes little difference from your perspective. Markdown is still available free of charge (more on this in a bit, though).
(If you’re not using Markdown, but might be interested, I encourage you to take a look as some example Markdown syntax. It’s the best way to “get” what it is that Markdown does. You can see my Markdown source for any Daring Fireball article by adding a ‘.text’ suffix to the URL of any article. E.g., to see the original Markdown source for this article, look here. I’ll explain how this trick works some other day.)
However, if you’re a developer who wishes to use Markdown as part of or in conjunction with your own project or app, my switching to the BSD should make this significantly easier — especially for other open source projects that are themselves licensed under BSD-style licenses.
Licensing discussions make me sleepy, so I’ll try to keep this short.
In a nut, the reason I originally chose the GPL for Markdown was that I had the vague, poorly-thought-out notion that Markdown could be available freely to users who simply wanted to use it, and to developers writing other open source projects. And that business users and developers writing non-open source projects who wanted to include Markdown might be willing to pay me some sort of reasonable fee to license Markdown under something other than the GPL.
That was just a notion, though. And in practice, using the GPL didn’t help with two of my goals:
Developers creating open source projects licensed under the BSD (or similar) felt like they couldn’t include Markdown under the GPL. That’s not what I want — I want other open source developers to feel free to use Markdown in their systems.
No commercial developers or business users volunteered to pay any license fees anyway.
The reason I was happy to do this, even though their apps aren’t free, is that it’s obvious that it’s the way it ought to be. Among Markdown users who use desktop weblog editors like Ecto and MarsEdit, there’s strong demand for “previewing” Markdown-formatted entries before publishing them to their weblogs. But due to the nature of current desktop weblog editing APIs, the only way for these apps to provide this feature is for the software to run a copy of Markdown locally.
But the irony of this is that non-open-source software like Ecto and MarsEdit are including Markdown for free, but the authors of several BSD-licensed open source projects feel they can’t include Markdown, on the grounds that they don’t believe they can include a GPL-licensed Perl script as part of a BSD-licensed project.
Switching to a BSD-style license makes things easy. If you want to use it, go ahead and download it, it’s free. If you want to use it as part of your own programming project, you may do so freely, with the only provisions being: (a) you must give me credit; and (b) you can’t use the name “Markdown” without my permission.
This licensing change also applies to Michel Fortin’s PHP Markdown port, version 1.0.1 of which should be released shortly, and which will also now be available under a BSD-style license.
As for making a few bucks from my efforts (read: cashing in on Markdown’s popularity), I put a PayPal donation form on the Markdown project page. If you enjoy Markdown and feel it’s worth a small contribution, I’d be delighted. I suspect the main reason people ignore online tip jars and donation boxes, even for projects they enjoy, is that they hope “someone else” is chipping in. So, I’ve also included a running tally of the total amount contributed by everyone. It should update “live” with each contribution. Can you make money giving away open source software? We’ll see.
What this means is that you get to set the price for Markdown. If you think it ought to be free, that’s fine, go ahead and use it for free, no strings attached. But if you think it’s worth $5, or $15, or $25 — you decide what to pay.
(And, even if the total remains pegged at or near $0, I’m not exactly coming away empty-handed. Because Markdown placed third in Six Apart’s Movable Type developer contest, I did win a 40 GB iPod and the Adobe Creative Suite.)
There have been a lot of good feature ideas for Markdown discussed on the Markdown-Discuss mailing list. Among the features I’d like to add for version 1.1:
<span>HTML tag. People want this so they can apply CSS classes and IDs to the parent tags, but still be able to write the contents in Markdown format.
citeattribute for blockquotes.
If this donation thing works, I might be able to spend time working on Markdown 1.1 sooner rather than later.