Bharti Airtel Limited, commonly known as Airtel, is an Indian multinational telecommunication services company headquartered in New Delhi, India. It operates in 20 countries across South Asia, Africa, and the Channel Islands. Airtel has GSM network in all countries in which it is present, providing 2G, 3G and 4G services depending upon the country of operation. Airtel is the world's fourth largest mobile telecommunication company by subscribers with over 275 million subscribers across 20 countries as of July 2013. Its B2C offer include mobile services, telemedia services, and digital TV while it further provides services to large enterprises and carriers as well as tower infrastructure services.