Vim can perform syntax highlighting for various file formats. You can enable it with these steps if it's not currently enabled;

Steps to enable syntax highlighting in Vim:

  1. Make sure full version of Vim with support for syntax highlighting is installed.

    Related: How to install full version of Vim on Red Hat / CentOS / Fedora
    How to install Vim on Ubuntu

  2. Enter command mode by pressing Esc.
  3. Type :syntax on|off and press Enter. 

    :syntax on

  4. Enter command mode again by pressing Esc

  5. Type :set syntax=<filetype> and press Enter manually set syntax for specific file type if required. 

    :set syntax=php

  6. View the list of supported file types while also in the command mode. 

    :echo getcompletion(// 'filetype')

  7. Permanently enable syntax highlighting by adding :syntax on in your ~/.vimrc file.