tak <file>
There are two kinds of modifiers. Control (C-) and Meta (M-). Meta is usually the Alt key, provided your terminal is sane. If your terminal is not sane, try Escape, then the shortcut key.
M-q Quit
M-s Save file
C-z Undo
C-k Kill (delete) current line
movement:
arrows move around lines and rows
PgUp/PgDn move up/down by a screen
Home beginning of line
End end of line
C-arrow-l/r move back or forwards by word (M-arrow-l/r also work)
C-arrow-u/d move up or down one paragraph (separated by blank lines)
(M-arrow-u/d also work)
M-S-g goto line
copy/paste:
C-space Begin selecting
C-g Cancel selecting
C-x Cut
C-c Copy
C-v Paste
Use C-space to begin a "region". Then use C-c to cut that region or C-c to copy it. Use C-v to paste at current insertion point.
The clipboard is saved to disk on quit, so when you reopen tak, the last copied text will be available to paste.
searching:
C-s Start searching
When searching, type a string to search for it in the file. Use C-s again to search for the next occurence. Any non-character key will quit searching.
other:
Tak uses utf-8 terminal routines. If your terminal is not utf-8 (unicode) aware, strange things might happen.
If this appears to be a marshmallow flipping a table over, your terminal should be fine:
(╯°□°)╯︵ ┻━┻