It is seen that the words of safety and security are being used interchangeably in daily use of language. Yet these are defined as a synonym in many dictionaries. On the other hand, for a long while, there has been an attempt to clarify in what way “security” differs from “safety” in terms of meaning in aviation and maritime transportation. Following definitions have been made in the academic literature in order to make a distinction between these two words. In conclusion, the definitions of “safety” and “security” will be considered. Safety : The state of being away from hazards caused by natural forces or human errors randomly. The source of hazard is formed by natural forces and/or human errors. Security : The state of being away from hazards caused by deliberate intention of human to cause harm. The source of hazard is posed by human deliberately.