Communication is commonly defined as the transmission of information. Its precise definition is disputed and there are disagreements about whether unintentional or failed transmissions are included and whether communication not only transmits meaning but also creates it. Models of communication are simplified overviews of its main components and their interactions. Many models include the idea that a source uses a coding system to express information in the form of a message. The message is sent through a channel to a receiver who has to decode it to understand it. The main field of inquiry investigating communication is called communication studies.

The history of communication technologies have evolved in tandem with shifts in political and economic systems, and by extension, systems of power. Communication can range from very subtle processes of exchange to full conversations and mass communication. The history of communication itself can be traced back since the origin of speech circa 100,000 BCE. The use of technology in communication may be considered since the first use of symbols about 30,000 years BCE. Among the symbols used, there are cave paintings, petroglyphs, pictograms and ideograms. Writing was a major innovation, as well as printing technology and, more recently, telecommunications and the Internet.