A landline (land line, land-line, main line, home phone, fixed-line, and wireline) is a telephone connection that uses metal wires or optical fiber telephone line for transmission, as distinguished from a mobile cellular network, which uses radio waves for signal transmission. Characteristics Landline service is typically provided through the outside plant of a telephone company's central office, or wire center. The outside plant comprises tiers of cabling between distribution points in the exchange area, so that a single pair of copper wire, or an optical fiber, reaches each subscriber location, such as a home or office, at the network interface. Customer premises wiring extends from the network interface to the location of one or more telephones inside the premises. The telephone connected to a landline can be hard-wired or cordless and typically refers to the operation of wireless devices or systems in fixed locations such as homes. Fixed wireless devices usually derive their electrical power from the utility mains electricity, unlike mobile wireless or portable wireless, which tend to be battery-powered. Although mobile and portable systems can be used in fixed locations, efficiency and bandwidth are compromised compared with fixed systems. Mobile or portable, battery-powered wireless systems can be used as emergency backups for fixed systems in case of a power blackout or natural disaster. Usage In 2003, the CIA World Factbook reported approximately 1.263 billion main telephone lines worldwide. China had more than any other country, at 350 million, and the United States was second with 268 million. The United Kingdom had 23.7 million residential fixed home phones. The 2013 statistics show that the total number of fixed-telephone subscribers in the world was about 1.26 billion. The number of landline subscribers continuously decreases due to upgrades in digital technology and the conveniences that come with switching to wireless (cellular) or Internet-based alternatives. Successors In many countries, landline service has not been readily available to most people. In some countries in Africa, the rise in cell phones has outpaced growth in landline service. Between 1998 and 2008, Africa added only 2.4 million landlines. In contrast, between 2000 and 2008, cell phone use rose from fewer than 2 in 100 people to 33 out of 100. There has also been a substantial decline of landline phones in the Indian subcontinent, in urban and even more in rural areas. In the early 21st century, the landline telephone has declined due to the