按i前插入字符。a在光标后追加字符

ctrl+d将光标下称半个窗体。按Ctrl+u将光标上移半个窗体

在输入模式下：ctrl+h删除字符，ctrl+u删除行。ctrl+w删除字

命令模式下。x删除字符。dw删除字，dd删除行

u表示撤销上一个操作

ctrl+r或输入命令:redo。表示重做

命令dw和i能够用一条命令cw（chang world）来实现。

命令cw能够使用VIM进入输入模式

$ vim -r memo

:w memo2

可将文件另存

dw: delete current word, but first thing for this command is the cursor has to be the first character of the word.

d$: delete to the end of the line

0: move to the end of the line.

d3w: delete the 3 words after the cursor. d4w will delete 4 words

U: To undo all the changes on a line

p: put the line which deleted by command 'dd' under the cursor line

r: Type rx to replace the character at the cursor with x

ce: To change until the end of a word, type ce

c$: Delete the context from cursor to the end of the line, and go the input mode

ctrl+g : To show your location in the file and the file status.

G: Go to the bottom of the file.

gg: To move you to the start of the file.

G: Type the number of the line you want to go and then G, this will go to the line you wann to go.

/: search for the phrase from forward

?

: search for the phrase from backward

n: search the same phrase again, simple type n

N: search the same phrase in the opposite direction, type N

ctrl+o: To go back to where you came from. Repeat to go back further

ctrl+i: To go forward

%: to find a matching ),], or }. This is very useful in debugging a program with unmatched parentheses

:s/old/new/ to substitute 'new' for 'old', only change the first occurrence

:s/old/new/g to substitute 'new' for 'old', will change all the occurrences in the line

:%s/old/new/g to change every occurrence in the whole file

:%s/old/new/gc to find every occurrence in the whole file, with a prompt whether to substitute or not

o: to open a line below the cursor and place you in insert mode.

O: to open a line above the cursor and place you in insert mode.

a: to insert text AFTER the cursor

i: to insert text BEFORE the cursor

A: to insert text at the end of line

R: replace more than one character

r: replace one character of cursor position

copy and paste: 

1. start visual mode with v and move the cursor to select the text you want to copy

2. Type y to yank(copy) the highlighted text.

3. Go to the position which you want to paste your text

4. Type p to put(paste) the text

set option:

:set number(set nu): show up line number

:set ic: set ignores case when searching or substitute

:set hls is: set lisearch and incsearch option

:set noic: disable ignoring case 

if you want to ignore case for just one search command, user \c in the phrase: /youString\c