Telstra Group Limited is an Australian telecommunications company that builds and operates telecommunications networks and markets voice, mobile, internet access, pay television and other products and services. It is a member of the S&P/ASX 20 and Australia's largest telecommunications company by market share. Telstra is the largest wireless carrier in Australia, with 18.8 million subscribers as of 2020. Telstra has a long history in Australia, originating together with Australia Post as the Postmaster-General's Department upon federation in 1901. Telstra has transitioned from a state-owned enterprise to a fully privatised company and has recently focused on diversified products and emerging technologies. History Australia's telecommunications services were originally controlled by the Postmaster-General's Department (PMG), formed in 1901 as a result of Australian Federation. Prior to 1901, telecommunications were administered by each colony. On 1 July 1975, separate commissions were established by statute to replace the PMG. Responsibility for postal services was transferred to the Australian Postal Commission (Australia Post). The Australian Telecommunications Commission (ATC), trading as Telecom Australia, ran domestic telecommunication services. In 1989, the ATC introduced new buildings and frameworks. In 1993, the Overseas Telecommunications Commission, a separate government body established in 1946, was merged with the Australian Telecommunications Corporation into the short-lived Australian and Overseas Telecommunications Corporation (AOTC) which continued trading under the established identities of Telecom and OTC. The AOTC was renamed to Telstra Corporation Limited in 1993. The name "Telstra" is derived from the word Telecom Australia (TEL from Telecom and STRA from Australia). The corporation then traded under the "Telstra" brand internationally and "Telecom Australia" domestically until uniform branding of "Telstra" was introduced throughout the entire organisation in 1995, following an unsuccessful attempt to register the trademark "Telecom Australia". Telstra has faced competition since the early 1990s from Optus (Australia's second largest communication company) and a number of smaller providers. Telstra once retained ownership of the fixed-line telephone network, but since the nationwide upgrade to the National Broadband Network (NBN), the Australian Government now has legal ownership of these lines since 2007, though Telstra has played a big part in this upgrade supplying resources to the Government on the new network. Telstra also has pay TV and owns 35% of the Australian media company Foxtel. Other companies offering fixed-line services must therefore deal with Telstra, except Optus, TransACT and a few others who have installed their own infrastructure. Overseas Telecommunications Commission The Overseas Telecommunications Commission (OTC) was