Vim is a free and open-source, screen-based text editor program. It is an improved clone of Bill Joy's vi. Vim's author, Bram Moolenaar, derived Vim from a port of the Stevie editor for Amiga and released a version to the public in 1991. - Wikipedia
How to install and use Vim text editor on CentOS7
To install the "Vim", execute the following command and see the images below.
sudo yum install vim
How to run VIM?
Let's make a new file and edit it with VIM by issuing the following command: Let's make a new file and edit it with VIM by issuing the following command:
$ vim VimExample.txt
How Do I Change the Content of a File?
To change VIM to edit mode, press "Shift +:" and then press 'i' to start edit mode:
How Do I Save the Content of a File?
To save the new changes, press "Esc" and then "W" following "Enter" (To quit without saving using 'q')
Note: A combination of 'wq' will save and quit the file in a single command.
For more great commands, please visit the official VIM Guide