A bit of history:
AFAICS, a lot of these concepts and terminology have been introduced by software from the GNU project (such as Emacs or Readline) very early, back when terms like “copy” or “paste” did not really exist, and keyboards were not standardized like they are today.
Although CUA is probably nowadays the major source of inspiration for most user interface designs (especially key bindings in GUIs), such Emacs-based key-bindings remain widely used in a lot of terminal-based UIs.
All this (not so interesting) discussion to get to one (potentially interesting) point: you might be able to find more detailed information about all this in any source of documentation related to Emacs.
All this looks correct. As you know, a binding like meta-w will be triggered when pressing simultaneously the Alt and w keys. But note that it should also be triggered when pressing Esc followed by w.
meta-< should mean Alt (or Option) in conjunction with whatever key-chord produces the less-than symbol (<). With an English QWERTY keyboard layout, this might be Alt+Shift+, (therefore the implied Shift key). But on my French AZERTY layout, this is simply Alt+<.
You’re right that there is some inconsistency in the way letter keys are denoted. Extracting some examples from the list you already mentioned:
meta-wrefers to Alt+wmeta-Wrefers to Alt+Shift+w (implied Shift in order to get the upper-caseW)meta-F: this should probably rather bemeta-fbecause it refers to Alt+f
I think bindings such as ^C or ^K always refer to Ctrl+letter without any implied Shift.
I might be wrong, but I don’t think there are any bindings with Ctrl+Shift+something (and if there were, it would probably be denoted differently).
The “region” is the part of text between the “mark” and the “point”. The “point” is the current position of the cursor; the mark is a position that you set beforehand using this ^-Space key binding. When the region is “active”, the text in it is highlighted, which makes it easier to visually follow what you’re doing. (But even when the region is not active, you can still use all commands which work on the region, like “killing” / “yanking”)
In short,
- the “kill ring” is like the “clipboard” in the terminology you’re probably used to (except that it can store several things, more on that below)
- “killing” is like “cutting” (i.e. delete some text but save it in the “kill ring”/“clipboard”)
- “yanking” is like “pasting” (retrieve some text from the “kill ring”/“clipboard” and insert it)
So Copy/Kill/Yank is more or less like Copy/Cut/Paste. It operates on the current region, as defined by the previously set “mark” and the current “point”. (And keep in mind that it operates whether the region is active or not).
^K is a specific “kill” operation which does not operate on the region, but rather “kills” all the text from the “point” to the end of the current line.
A difference between the “kill ring” and the clipboard is that the kill ring saves several entries. When you yank something using ^Y, you retrieve by default the last killed text. But if you want to retrieve some older entry instead, you can then press meta-y to yank the second-to-last entry instead. And additional meta-y yank increasingly older entries from the kill-ring, until you get to the one you want and resume normal editing (by pressing anything other than meta-y).