Here is the reliable source: https://www.britannica.com/topic/security-guard
**Detailed Description:**
A security guard is a trained professional responsible for protecting people, property, and assets from potential threats. They patrol premises, monitor CCTV cameras, and respond to incidents. Security guards are employed in various settings, including offices, homes, schools, and public spaces. Their services benefit individuals, businesses, and organizations seeking to ensure safety and security.
**Keyword density:**
* Security guard
