vim is a very light and easily customizable editor.
i
Enter insert mode
a
Append
:q - Quit
:wq - Write/Save and quit
h - Left
l- Right
j- Down
k- Up
$ - Move to end of a line
^ - Move to begining of a line
shift+i - Insert at begining of the line
shift+a - Insert at end of line (append)
c - Change(Delete and enter into insert mode)
ci - Change in (eg:-'ci(' changes everything inside the brackets)
ciw - Change in a word(the cursor can be anywhere on the word)
ca - Change and (eg:-'ca(' Deletes everything inside the brackets along with the bracket and enters insert mode)
c$ - Change till end(from cursor point)
x - Delete the character pointed by the cursor
dd - Delete a line
diw - Delete in a word
di - Delete in
da - Delete and
d$ - Delete till end(from the cursor position)
y - Yank
*y - Yank such that you can paste it even outside vim
v - Visually select (enters visual mode)
shift+v - Visually select a block
?word - Searches the word in file
:vsplit - Vertical split
:split - Horizontal split
ctrl+n - Autocompletion option
Shift+v,y - yank selected text
:%s/old/new/g - replace old with new in the entire file
:%s/old/new/gc - replace old with new in the entire file, with a prompt asking you for confirmation for each word.
10j - move 10 times down(you can replace 10 with any number and j with other motions(h,k,l))