Since Version 2.5 WordPress support so called Shortcodes. They have been introduced for creating macros to be use in a posts content. This Video tutorial will teach you how to create custom WordPress shortcodes
More video
Shortcodes WordPress
Hardcode your Shortcode
Further Reading
WordPress Shortcodes: A Complete Guide
WordPress Shortcodes: The Right Way
How to Add A Shortcode in WordPress?
Codex Shortcode
