This is a cheat sheet for the text editor Vim. If you want to learn Vim, I strongly recommend you to start out with doing vimtutor.

A short note: Vim works by combining operators with (optional numbers and) motions. To abort what you're doing (leaving Insert mode or Visual mode, aborting an operation, etc.) press <ESC>; Ctrl+c usually works too.

Motions:

w moves to first character of next word;
b moves to first character of current or previous word;
e moves to last character of current or next word;
0 moves to the first character of line;
^ moves to first non-blank character of line;
$ moves to last character of line;
t{char} moves forward on the line to the position before the character entered after t;
T{char} moves backward on the line to the position before the character entered after T;
f{char} moves forward on the line to the position of the character entered after f;
F{char} moves backward on the line to the position of the character entered after F;
These motions can be appended to a number to repeat the movement;

gg goes to first line of file;
G goes to last line of file;
Ctrl+g displays current line position of cursor and total number of lines of file;
{line}G or {line}gg where {line} is the number of the line where you want to place the cursor;

Insert mode:

i enters insert mode at cursor location;
a enters insert mode one step AFTER cursor position (ea appends to current word);
I prepends to line, i.e. enters insert mode at the first non-blank character of line;
A appends to line, i.e. enters insert mode AFTER the end of the line;
o opens the line below the cursor and enters Insert mode;
O opens the line above the cursor and enters Insert mode;
r replaces the symbol the cursor is placed on with the symbol entered after r.
R replaces multiple symbols with the ones entered after R, starting where the cursor was placed and stopping when pressing <ESC>.
Ctrl+w deletes a whole word before the cursor while in Insert mode;
Ctrl+u deletes the line before the cursor while in Insert mode;

Visual selection mode:

v enter Visual mode, where you can mark text by using motions, which can be deleted, yanked (copied), saved to a new file named NAME (by typing :w NAME after text has been marked).
V enters Visual Line mode with whole lines are being marked;
Ctrl+v enters Visual Block mode where rectangular blocks are marked. End with <ESC> to apply the following operations: ** to insert text, use Shift+i; ** to change text, use c; ** to delete text, use d or x (this will be applied right away followed by exiting Visual Block mode);

Cutting, copying, pasting using Vim's clipboard:

d followed by motion to cut text: dd to cut a whole line;
D or d$ to cut rest of line;
c followed by motion cuts the chosen text and enters Insert mode: cc cuts the whole line;
x to cut a single character;
y followed by motion to copy (AKA 'yank') text: yy to yank a whole line
p pastes text from Vim's clipboard, inserting it after the cursor;
P pastes text from Vim's clipboard, inserting it after the cursor;
The above operators can be used when text has been marked in Visual mode;

Edit:

u undo last operation;
Ctrl+r to redo undone operation;
>> indents line where cursor is placed, > indents text marked via Visual mode;
<< dedents line where cursor is placed, < dedents text marked via Visual mode;

Commands:

:w to save;
:w NAME to save to not pre-existing file named NAME, either saving the whole file or only the text marked via visual mode;
:q! to quit without saving changes;
:wq to save and quit;
:r NAME to insert content of file NAME in line below the cursor;
:r !{external command} reads from command and puts it below the cursor position;

Cutting, copying, pasting using system clipboard:

Shift+Ctrl+v or "+p pastes text to the file from the system clipboard;
Shift+Ctrl+x or "+x cuts text from the file to the system clipboard;
Shift+Ctrl+c or "+c copies text from the file to the system clipboard;
Explanation: In the second alternative of the operations above, the system clipboard is interacted with by entering " (the registers symbol), then + to access the clipboard register, followed by what we want to do with the clipboard;

Search, find, replace:

:/ followed by a search word followed by <Enter> to find the first instance of the word, followed by n to continue search forward or N to continue search backward;
:? works like / but starts to search backward right away after <Enter>;
:s/old/new substitutes new for old at the first match found: append with /g to do it for the whole line;
:%s/old/new/g replaces every occurence in the whole file;
:%s/old/new/gc finds all occurances in the file and asks whether you want to replace them;
:#,#s/old/new/g replaces old for new between lines #,#;
% to find matching ), ], or } which cursor is placed on;
:set ic to set search to ignore case (:set ignorecase also works);
:set noic to set search to not ignore case;
:/SEARCHWORD\c to search for SEARCHWORD and ignoring cases in just that search;
:set hls is to enable highlighting of matches in search (:set hlsearch also works);
:set nohls is to disable highlighting of matches in search;
TODO: What does :set is do? So called insearch;

Execute external commands:

:!{external command} followed by <Enter> runs any external shell command, such as ls -a or dir;

Completion:

Starting to write a command, like :e followed by <TAB> autocompletes it in alphabetical order, such as the case in most shells and terminals. Pressing Ctrl+d displays all possible completions.

Navigating directories

Running vim . in a terminal opens a directory listing that can be navigated with j, k and <Enter>. To create a new file, press %; to create a new directory, press d. To return to this view from a file that has been entered from here, use :Ex. External commands can be run by :! {command}.

Vim cheat sheet