Vim is a powerful text editor and it is the most popular one for Linux users.
For details of it you can go to https://en.wikipedia.org/wiki/Vim_%28text_editor%29

And Vim is usually installed as defaut for Ubuntu users. You only need to type “vim” in the terminal and you can get access to it. I’ve been using it for about two weeks and it really appeals to me. I’ll show some common using method of it here.

1. First of all, type:
vim file_name
then you will have a document named “file_name” in your current folder.

2. It has many modes:
type “i” and you can get into “insert” mode, you can put in your code at the cursor’s place
and type different command will enable you to insert at different places:
Iinsert at the head of the current line
ainsert at the right side of the current place
A: insert at the tail of the current line
oinsert a new line at the up side
Oinsert a new line at the down side
set ai
set si

3. If you press “Esc” you will get into another mode.
Then tpye
:w #save
:wq #save and leave, and you can also press “Shift” + “Z” + “Z”
dd #to delete the curren line

4. You can modify the settings of vim by edit “.vimrc” in your home”
colorscheme desert #to change the colorscheme, for more scheme:
set tabstop=4 #to change the width of Vim
set number #to add line number
set ai
set si #to enable the automatic indentation
map<F12><Esc>:!”python” %