A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from Greek: τῆλε and φωνή, together meaning distant voice. A common short form of the term is phone, which came into use early in the telephone's history. Nowadays, phones are almost always in the form of smartphones or mobile phones, due to technological convergence.
In telephony, ringdown is a method of signaling an operator in which telephone ringing current is sent over the line to operate a lamp or cause the operation of a self-locking relay known as a drop.
Enhanced 911 is a system used in North America to automatically provide the caller's location to 911 dispatchers. 911 is the universal emergency telephone number in the region. In the European Union, a similar system exists known as E112 and known as eCall when called by a vehicle.
An emergency telephone number is a number that allows a caller to contact local emergency services for assistance. The emergency number differs from country to country; it is typically a three-digit number so that it can be easily remembered and dialed quickly. Some countries have a different emergency number for each of the different emergency services; these often differ only by the last digit.
A payphone is typically a coin-operated public telephone, often located in a telephone booth or in high-traffic public areas. Prepayment is required by inserting coins or telephone tokens, swiping a credit or debit card, or using a telephone card.
999 is an official emergency telephone number in a number of countries which allows the caller to contact emergency services for emergency assistance. Countries and territories using the number include Bahrain, Bangladesh, Botswana, Eswatini, Ghana, Guernsey, Hong Kong, the Republic of Ireland, the Isle of Man, Jersey, Kenya, Macau, Malaysia, Mauritius, Poland, Qatar, Sudan, Saudi Arabia, Singapore, Trinidad and Tobago, Seychelles, Uganda, the United Arab Emirates, the United Kingdom, and Zimbabwe.
Operator assistance refers to service provided by a telephone operator to the calling party of a telephone call. This can include telephone calls made from pay phones, calls placed station-to-station, person-to-person, or collect, third-number calls, calls billed to credit cards, and certain international calls which cannot be dialed directly. The telephone operator may also be able to assist with determining what kind of technical difficulties are occurring on a phone line, to verify whether a line is busy, or left off the hook, or to break in on a live call to ask the caller to clear the line for an incoming call. The latter service is often utilized by emergency police. In addition, operators are often a first point of contact for the elderly wanting information on the current date and time.
A call box or callbox is a box containing a special-purpose direct line telephone or other telecommunications device which has been used by various industries and institutions as a way for employees or clients at a remote location to contact a central dispatch office.
His Majesty's Coastguard (HMCG) is the section of the Maritime and Coastguard Agency responsible, through the Secretary of State for Transport to Parliament, for the initiation and co-ordination of all maritime search and rescue (SAR) within the UK Maritime Search and Rescue Region. This includes the mobilisation, organisation and tasking of adequate resources to respond to persons either in distress at sea, or to persons at risk of injury or death on the cliffs or shoreline of the United Kingdom. Since 2015 it has also been responsible for land-based search and rescue helicopter operations.
Base station is – according to the International Telecommunication Union's (ITU) Radio Regulations (RR) – a "land station in the land mobile service."
111 is the emergency telephone number in New Zealand. It was first implemented in Masterton and Carterton on 29 September 1958, and was progressively rolled out nationwide with the last exchanges converting in 1988.
A cellular network or mobile network is a telecommunications network where the link to and from end nodes is wireless and the network is distributed over land areas called cells, each served by at least one fixed-location transceiver. These base stations provide the cell with the network coverage which can be used for transmission of voice, data, and other types of content. A cell typically uses a different set of frequencies from neighboring cells, to avoid interference and provide guaranteed service quality within each cell.
Mobile telephony is the provision of telephone services to mobile phones rather than fixed-location phones. Telephony is supposed to specifically point to a voice-only service or connection, though sometimes the line may blur.
An intercom, also called an intercommunication device, intercommunicator, or interphone, is a stand-alone voice communications system for use within a building, small collection of buildings or portably within a small coverage area, which functions independently of the public telephone network. Intercoms are generally mounted permanently in buildings and vehicles, but can also be detachable and portable. Intercoms can incorporate connections to public address loudspeaker systems, walkie talkies, telephones, and other intercom systems. Some intercom systems incorporate control of devices such as signal lights and door latches.
000 Emergency, also known as Triple Zero or Triple 0, and sometimes stylised Triple Zero (000), is the primary national emergency telephone number in Australia and Australian External Territories. The Emergency Call Service is operated by Telstra, and overseen by the Australian Communications and Media Authority (ACMA), and is intended only for use in life-threatening or time-critical emergencies.
A party line is a local loop telephone circuit that is shared by multiple telephone service subscribers.
A bat phone or batphone, in popular jargon, is a private telephone number for important telephone calls handled at high priority. The term is also used to describe the use of more than one mobile phone, with the "bat phone" reserved for a specific purpose. The name Bat-Phone was popularized by the Batman television series starting in 1966, when it was depicted as a red phone that Commissioner Gordon used to summon the superhero Batman in emergencies, and as the red phone mounted inside the Batmobile, the car driven by Batman. Technology journalists have also used "Bat Phone" to describe devices that are novel in appearance, or have a connection to the Batman franchise.
Illegal taxicabs, sometimes known as pirate taxis, gypsy cabs, or jitney cabs, are taxicabs and other for-hire vehicles that are not duly licensed or permitted by the jurisdiction in which they operate. Most major cities worldwide require taxicabs to be licensed, safety-inspected, insured as for-hire vehicles, and to use taximeters, and there may also be requirements that the taxi driver be registered or accredited. However, many unlicensed cabs are in operation. Illegal cabs may be marked taxi vehicles, and others are personal vehicles used by an individual to offer unauthorized taxi-like services. Illegal cabs are prevalent in cities with medallion systems, which restrict the number of legal cabs in operation. Since their introduction in 2009, vehicles affiliated with ridesharing companies have been classified as illegal taxicabs in some jurisdictions.
A telephone number is a sequence of digits assigned to a landline telephone subscriber station connected to a telephone line or to a wireless electronic telephony device, such as a radio telephone or a mobile telephone, or to other devices for data transmission via the public switched telephone network (PSTN) or other public and private networks.
Telephone interpreting connects human interpreters via telephone to individuals who wish to speak to each other but do not share a common language. The telephone interpreter converts the spoken language from one language to another, enabling listeners and speakers to understand each other. Interpretation over the telephone most often takes place in consecutive mode, which means that the interpreter waits until the speaker finishes an utterance before rendering the interpretation into the other language. As the use of the telephonic modality is increasing it is allowing users to access an interpreter immediately, regardless of time and location.
