* Left / Right (or CTRL-b / CTRL-f):
  - move insertion cursor one character to the left or right
  - clear selection

* CTRL-Left / CTRL-Right (or META-b / META-f):
  - move insertion cursor by words

* SHIFT-Left / SHIFT-Right:
  - move insertion cursor by characters, extend selection

* CTRL-SHIFT-Left / CTRL-SHIFT-Right
  - move insertion cursor by words, extend selection

===============================================================================
* Up / Down (or CTRL-p / CTRL-n):
  - move insertion cursor one line up or down
  - clear selection

* CTRL-Up / CTRL-Down:
  - move insertion cursor by paragraphs (groups of lines separated by
    blank lines)

* SHIFT-Up / SHIFT-Down:
  - move insertion cursor, extend selection

* CTRL-SHIFT-Up / CTRL-SHIFT-Down:
  - move insertion cursor by paragraphs (groups of lines separated by
    blank lines), extend selection

===============================================================================
* CTRL-v:
  - move view down one screen

* Next / Prior:
  - move insertion cursor forward or backwards by one screen
  - clear selection

* SHIFT-Next / SHIFT-Prior:
  - extend selection by character

* CTRL-Next / CTRL-Prior:
  - scroll view right or left by one page

* Home (or CTRL-a):
  - move insertion cursor to beginning of its line
  - clear selection

* SHIFT-Home:
  - moves insertion cursor to beginning of line
  - extend selection to beginning of line

* End (or CTRL-e):
  - move insertion cursor to end of line
  - clear selection
  
* SHIFT-End:
  - move cursor to end of line
  - extend selection to end of line

* CTRL-Home and META-<:
  - move insertion cursor to beginning of text
  - clear selection

* CTRL-SHIFT-Home:
  - move insertion cursor to beginning of text
  - extend selection to beginning of text

* CTRL-End and Meta->:
  - move insertion cursor to end of text
  - clear selection

* CTRL-SHIFT-End:
  - move cursor to end of text
  - extend selection to end of text

===============================================================================
* Select (or CTRL-Space):
  - set selection anchor to position of insertion cursor

* SHIFT-Select (or CTRL-SHIFT-Space):
  - adjust selection to current position of insertion cursor
   (select from anchor to insertion cursor if no previous selection)

* CTRL-/:
  - select all

* CTRL-\:
  - clear selection

* META-w (or F16, labelled Copy on many Sun workstations):
  - copy selection to clipboard
 
* CTRL-w (or F20, labelled Cut on many Sun workstations):
  - copy selection to clipboard
  - delete selection

* CTRL-y (or F18, labelled Paste on many Sun workstations):
  - insert contents of clipboard at position of insertion cursor

* Delete:
  - delete selection
    (if no selection, delete character to right of insertion cursor)

* Backspace (or CTRL-h):
  - delete selection
    (if no selection, delete character to left of insertion cursor)

* CTRL-d:
  - delete character to right of insertion cursor

* META-d:
  - delete word to right of insertion cursor

* CTRL-k:
  - delete from insertion cursor to end of its line
    (if insertion cursor is at end of line, delete newline character)
  - place deleted text in clipboard

* CTRL-o
  - open new line

* META-Backspace (or META-Delete)
  - delete word to left of insertion cursor

* CTRL-x
  - delete selected text
  - place deleted text in clipboard

* CTRL-t
  - reverse order of two characters to right of insertion cursor

* CTRL-z (or CTRL-_ on UNIX when tk_strictMotif is true)
  - undo last edit action

* CTRL-Z (or CTRL-y on Windows)
  - redo last undone edit action

