Security guards are usually not as thoroughly trained as security officers. They are used to guard such places as lumber yards and similar environments where not a huge amount of critical thinking is required. Officers often have security clearances since they are often found providing security for government installations and important officer buildings. They are better paid, as well.
Here I am sharing the main between a security guard and a security officer
Security guards : Security guards work in public and private buildings, as well as retail and wholesale establishments. Some work at transportation facilities guarding against potential terrorist attacks.
Security officers : Security officers provide monitoring services for property owners to provide a safe environment and prevent violence. A security officer plays many different roles, but his primary task is to prevent crime. The presence of a security officer on the premises often serves as a deterrent to potential lawbreakers.
Actually in the mean time I took a Security Guard Service from magnumprotective.com/, then I got to know something about security officers and the security guards. The security officers are doing planning how to provide best services; they are making some rules and security guards just obeying these rules by implementing those plannings.