Keyboard "shortcuts" for textareas

I do a lot of editing in textareas (like now) and I want keyboard shortcuts much like editors. Many keyboard shortcuts are built in to every text input, so learning them can be useful for such times.

Basic ones include arrow keys, though these aren't very ergonomic and they move slowly. To move the cursor faster, hold control, then left and right move by words and up / down go to the start / end of the line.

Backspace deletes backwards of course; delete deletes forwards. Like with arrows, holding control makes backspace and delete delete by words.

Holding shift and then pressing arrow keys creates a selection. Once you have a selection you can delete it, copy it, cut it etc.

Undo is control+z and redo is control+shift+z.

To to to the start of a line, I don't use the control up / down (because I just discovered it now; I might use it actually). Instead I use up arrow then right arrow. End of line is similar: down arrow then left arrow, or just down arrow if you're at the end of the input.

Editors have keyboard shortcuts like transpose characters and transpose words. I created a firefox extension for transposing characters which uses control+t; I don't find I transpose words much.

Pressing tab moves the focus to the next input, and pressing space presses the currently focused button. Control+return sometimes submits the form; shift+enter sometimes creates a new line when pressing return would submit (such as in messaging applications).