I maintain my Unix website on, presently, a Mac. Can I maintain it from a (not jailbroken) iPad 3? I have a website at JonathansCorner.com, which for the most part is a static collection of files, mostly HTML5, served up by a Linux Apache server. Maintaining it is mostly a matter of creating new HTML5 files and of updating existing files on my computer, used partly as a staging site, before being sftp'ed over to the server. Technologically the site is not particularly interesting; it's the content if anything that draws people.

Moving from maintaining my website on a Linux server to keeping it on a Mac was a piece of cake; Mac is my favorite Unix.

But I wanted to ask: Can I maintain, expand, and update my website on any iPad that has not been jailbroken? I recognize that the wrong way to go about the problem would be to go to search for the closest the App store has for my favorite editor, and for providing or emulating a heirarchy of files, and then sftp over. That may not be possible even on a jailbroken iPad, and it has the character of what woodenly word-for-word renderings are criticized for in translations that try to preserve the Greek word order or what have you as far as possible without pointedly breaking English grammar. What I have outlined may be appropriate on a Mac, but if the question is "How can I best use an iPad," it's barking up the wrong fire hydrant.

What I did want to ask is whether there is some dynamic equivalent that would be possible on the iPad. At very least the iPad should have multiple good options for composing something you're writing and emailing it to someone, perhaps to yourself. And composing in a nice editor and then converting plain text to HTML is a significant offering, or the pedestrian route of making a webmin interface to my site and try to optimize it for my iPad, and I imagine something like these might constitute the best way afforded by my iPad to pursue this interest, but maybe something better is available.

What are the best iPad offerings to facilitate "Compose it with your iPad and then post it as a handcoded webpage?" (What would you do if you wanted to use an iPad to expand and maintain a website consisting of an extensive collection of HTML documents and other static content, such as JonathansCorner.com?
Sounds like Diet Coda would be right up your alley. It's an iPad rethinking of the highly regarded Mac App Coda.

Basically it's everything you need to do hand coding of websites in one app package — a text editor for coding, (S)FTP for file management, and SSH for any server-side tasks. That's a pretty bare-bones description, there are a lot of well polished details that you may appreciate, I suggest checking out the site for more information.
You may also be interested in reviews from Macworld and Macstories.
Backups
It's worth noting that Diet Coda doesn't store the site resources on your iPad (it may cache some for performance reasons, but no permanent storage), all editing is done directly on the server. For this reason, it's probably best to have a backup of your website stored elsewhere if you don't already. This could be your Mac, but you could keep it all online by using something like Amazon S3. From the looks of your site (it appears to be just HTML and images, no big downloads, etc.), you could almost certainly keep a backup there for just over a dollar per year. It would be easy enough to set up an rsync script to automatically back up your site on a regular schedule to S3, and even keep snapshotted versions, you wouldn't really have to do anything beyond the initial set up.