Communication networks

The essentials

Communication helps people exchange messages, ideas and information. Personal communication includes letters, telephone calls, e-mail and mobile messages. Mass communication includes radio, television, newspapers, films, satellites and the internet, which reach many people at once.

The Indian postal network is among the largest in the world, handling letters, parcels and money transfers. Telephone and mobile networks have grown rapidly, especially in cities, and are now reaching rural areas.

Key points

• Radio: broadcasting started in 1923 with the Radio Club of Bombay; the government took it over, and it became All India Radio in 1936 and Akashvani in 1957.
• Television: Doordarshan began as an experiment in Delhi in 1959; it was separated from All India Radio in 1976 and became the national broadcaster.
• Satellites: India has two main systems – the Indian National Satellite System (INSAT), a multipurpose system for telecommunication, meteorology and broadcasting, and the Indian Remote Sensing (IRS) satellites for resource survey and management.
• Remote sensing data are processed at the National Remote Sensing Centre in Hyderabad and used for agriculture, forestry, water resources, disaster management and mapping.
• Internet: has made e-mail, online education, e-governance and e-commerce possible, and is linking even remote regions.
• Newspapers are published in many Indian languages, reflecting the country's diversity.

Exam tips

Remember the radio and television milestones and the difference between INSAT (communication and weather) and IRS (resource monitoring).

Common mistakes

IRS satellites are not mainly for telephone calls; they are for observing and mapping the earth's resources.