You have typed %THIS-KEY%, the help character. Type a Help option:
(Use SPC or DEL to scroll through this text. Type q to exit the Help command.)
a PATTERN Show commands whose name matches the PATTERN (a list of words
or a regexp). See also the `apropos' command.
b Display all key bindings.
c KEYS Display the command name run by the given key sequence.
C CODING Describe the given coding system, or RET for current ones.
d PATTERN Show a list of functions, variables, and other items whose
documentation matches the PATTERN (a list of words or a regexp).
e Go to the *Messages* buffer which logs echo-area messages.
f FUNCTION Display documentation for the given function.
F COMMAND Show the on-line manual's section that describes the command.
g Display information about the GNU project.
h Display the HELLO file which illustrates various scripts.
i Start the Info documentation reader: read on-line manuals.
I METHOD Describe a specific input method, or RET for current.
k KEYS Display the full documentation for the key sequence.
K KEYS Show the on-line manual's section for the command bound to KEYS.
l Show last 300 input keystrokes (lossage).
L LANG-ENV Describes a specific language environment, or RET for current.
m Display documentation of current minor modes and current major mode,
including their special commands.
n Display news of recent Emacs changes.
p TOPIC Find packages matching a given topic keyword.
r Display the Emacs manual in Info mode.
s Display contents of current syntax table, plus explanations.
S SYMBOL Show the section for the given symbol in the on-line manual
for the programming language used in this buffer.
t Start the Emacs learn-by-doing tutorial.
v VARIABLE Display the given variable's documentation and value.
w COMMAND Display which keystrokes invoke the given command (where-is).
. Display any available local help at point in the echo area.
C-a Information about Emacs.
C-c Emacs copying permission (GNU General Public License).
C-d Instructions for debugging GNU Emacs.
C-e External packages and information about Emacs.
C-f Emacs FAQ.
C-m How to order printed Emacs manuals.
C-n News of recent Emacs changes.
C-o Emacs ordering and distribution information.
C-p Info about known Emacs problems.
C-t Emacs TODO list.
C-w Information on absence of warranty for GNU Emacs.