• query-replace (M-%)
• query-replace-regexp (C-M-%)

Key	Description	Note
y	replace and advance
,	replace and stay
!	replace remaining in buffer or region	multi-buffer
Y	replace remaining across buffers	multi-buffer
n	skip
N	skip to next buffer	multi-buffer
C-l	re-center
u	undo
U	undo all
C-r	recursive edit: pause	C-M-c to resume
C-w	recursive edit: delete match and pause	C-M-c to resume
e	edit replacement string, replace, and continue
q	exit	also RET like in isearch

Re-centering with C-l works as well.

1. Query string
   • history: previous query-replacement pairs
   • future history:
     1. the word at point, if any
     2. the last successful isearch string
     3. previous query and replacement strings
2. Replacement string
   • history:
     1. the query string
     2. previous query and replacement strings
   • future history:
     1. the query string

(Search history with C-r and C-s, and navigate it with M-p and M-n.)