Abstract: Information is measurable physical quantity, such as mass, heat or any other form of energy. It is the choice of one massage out of finite set of massage. Meaning is immaterial in this sense. Information dissemination is as old as man. Ability to communicate meaningfully and intelligently among people differentiates human beings from animals. In the olden days, man used pigeons and men ride on horses to deliver mail. There had existed some channels of making meaningful transfer of information in form of facts and useful ideas through diverse kinds of tangible and intengile media. These various means of communication were very primitive. This study titled Communication System however presents a brief history of communication system, the basic transmission and reception system, classification of communication system/lines. The study further argues the advantage of the digital transmission system over the analog systems and the modern communication system/equipment vis-a-vis Telephone system and the Global System for Mobile Communication (GSM). Some advantages/benigfits and services offered by the GSM were also highlighted.