WordPress Plugins are PHP scripts that improve your WordPress website functionality which can be uploaded to your WordPress install without having to hack the core code.
All WordPress pluigns are PHP files, located in the <WORDPRESS-INSTALLATION>
/wp-content/plugins/ directory. In our example, the file will be called myPlugin
.php . I assume you’re comfortable with connecting to your server using FTP/SFTP/SCP or SSH.
Plugin Name: My Plugin Name
Plugin URI: http://ncircles.com
Description: Simple tutorial to create wordpress plugin
Author: Mahmoud Elsaid
// the plugin code will be here..
echo "Print my Text :)";
then install this file to your WordPress installation.
then you will see
Print my Text :)
in each page.