Telecom stocks are shares of publicly traded companies that provide voice, data and internet communication services over wired and wireless networks. These companies had the highest dollar trading volume of any Telecom stocks within the last several days. Get alerts:AT&T (T)AT&T, Inc. is a holding company, which engages in the provision of telecommunications and technology services. de C.V. provides telecommunications services in Latin America and internationally. The company offers wireless and fixed voice services, including airtime, local, domestic, and international long-distance services; and network interconnection services.