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Telephone
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 el, τῆλε (''tēle'', ''far'') and φωνή (''phōnē'', ''voice''), together meaning ''distant voice''. A common short form of the term is ''phone'', which came into use early in the telephone's history. In 1876, Alexander Graham Bell was the first to be granted a United States patent for a device that produced clearly intelligible replication of the human voice at a second device. This instrument was further developed by many others, and became rapidly indispensable in business, government, and in households. The essential elements of a telephone are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexander Graham Bell
Alexander Graham Bell (, born Alexander Bell; March 3, 1847 – August 2, 1922) was a Scottish-born inventor, scientist and engineer who is credited with patenting the first practical telephone. He also co-founded the American Telephone and Telegraph Company (AT&T) in 1885. Bell's father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf; profoundly influencing Bell's life's work. His research on hearing and speech further led him to experiment with hearing devices which eventually culminated in Bell being awarded the first U.S. patent for the telephone, on March 7, 1876. Bell considered his invention an intrusion on his real work as a scientist and refused to have a telephone in his study. Many other inventions marked Bell's later life, including groundbreaking work in optical telecommunications, hydrofoils, and aeronautics. Bell also had a strong influence on the National Geographic Society and it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Number
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. A telephone number serves as an address for switching telephone calls using a system of destination code routing. Telephone numbers are entered or rotary dial, dialed by a calling party on the originating telephone set, which transmits the sequence of digits in the process of signaling to a telephone exchange. The exchange completes the call either to another locally connected subscriber or via the PSTN to the called party. Telephone numbers are assigned within the framework of a national or regional telephone numbering plan to subscribers by telephone service operators, which may be commercial entities, state-controlled administrat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Public Switched Telephone Network
The public switched telephone network (PSTN) provides infrastructure and services for public telecommunication. The PSTN is the aggregate of the world's circuit-switched telephone networks that are operated by national, regional, or local telephony operators. These consist of telephone lines, fiber optic cables, microwave transmission links, cellular networks, communications satellites, and undersea telephone cables, all interconnected by switching centers which allow most telephones to communicate with each other. Originally a network of fixed-line analog telephone systems, the PSTN is now almost entirely digital in its core network and includes mobile and other networks, as well as fixed telephones. The technical operation of the PSTN adheres to the standards created by the ITU-T. These standards allow different networks in different countries to interconnect seamlessly. The E.163 and E.164 standards provide a single global address space for telephone numbers. The com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telecommunication
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that feasible with the human voice, but with a similar scale of expediency; thus, slow systems (such as postal mail) are excluded from the field. The transmission media in telecommunication have evolved through numerous stages of technology, from beacons and other visual signals (such as smoke signals, semaphore telegraphs, signal flags, and optical heliographs), to electrical cable and electromagnetic radiation, including light. Such transmission paths are often divided into communication channels, which afford the advantages of multiplexing multiple concurrent communication sessions. ''Telecommunication'' is often used in its plural form. Other examples of pre-modern long-distance communication included audio messages, such as code ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AT&T Push Button Telephone Western Electric Model 2500 Dmg Black
AT&T Inc. is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the world's largest telecommunications company by revenue and the third largest provider of mobile telephone services in the U.S. , AT&T was ranked 13th on the ''Fortune'' 500 rankings of the largest United States corporations, with revenues of $168.8 billion. During most of the 20th century, AT&T had a monopoly on phone service in the United States. The company began its history as the American District Telegraph Company, formed in St. Louis in 1878. After expanding services to Arkansas, Kansas, Oklahoma and Texas, through a series of mergers, it became Southwestern Bell Telephone Company in 1920, which was then a subsidiary of American Telephone and Telegraph Company. The latter was a successor of the original Bell Telephone Company founded by Alexander Graham Bell in 1877. The American Bell Telephone Company formed the American Telep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earphone
Headphones are a pair of small loudspeaker drivers worn on or around the head over a user's ears. They are electroacoustic transducers, which convert an electrical signal to a corresponding sound. Headphones let a single user listen to an audio source privately, in contrast to a loudspeaker, which emits sound into the open air for anyone nearby to hear. Headphones are also known as earspeakers, earphones or, colloquially, cans. Circumaural ('around the ear') and supra-aural ('over the ear') headphones use a band over the top of the head to hold the speakers in place. Another type, known as earbuds or earpieces consist of individual units that plug into the user's ear canal. A third type are bone conduction headphones, which typically wrap around the back of the head and rest in front of the ear canal, leaving the ear canal open. In the context of telecommunication, a headset is a combination of headphone and microphone. Headphones connect to a signal source such as an au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telephone Switchboard
A telephone switchboard was a device used to connect circuits of telephones to establish telephone calls between users or other switchboards, throughout the 20th century. The switchboard was an essential component of a manual telephone exchange, and was operated by switchboard operators who used electrical cords or switches to establish the connections. The electromechanical automatic telephone exchange, invented by Almon Strowger in 1888, gradually replaced manual switchboards in central telephone exchanges around the world. In 1919, the Bell System in Canada also adopted automatic switching as its future technology, after years of reliance on manual systems. Nevertheless, many manual branch exchanges remained operational into the second half of the 20th century in many enterprises. Later electronic devices and computer technology gave the operator access to an abundance of features. A private branch exchange (PBX) in a business usually has an attendant console, or an au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mobile Phone
A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive telephone call, calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture and, therefore, mobile telephones are called ''cellular telephones'' or ''cell phones'' in North America. In addition to telephony, digital mobile phones (2G) support a variety of other GSM services, services, such as text messaging, Multimedia Messaging Service, multimedia messagIng, email, Internet access, short-range wireless communications (Infrared Data Association, infrared, Bluetooth), business applications, video games and dig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microphone
A microphone, colloquially called a mic or mike (), is a transducer that converts sound into an electrical signal. Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, and radio and television broadcasting. They are also used in computers for recording voice, speech recognition, VoIP, and for other purposes such as ultrasonic sensors or knock sensors. Several types of microphone are used today, which employ different methods to convert the air pressure variations of a sound wave to an electrical signal. The most common are the dynamic microphone, which uses a coil of wire suspended in a magnetic field; the condenser microphone, which uses the vibrating diaphragm as a capacitor plate; and the contact microphone, which uses a crystal of piezoelectric material. Microphones typi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Handset
A handset is a component of a telephone that a user holds to the ear and mouth to receive audio through the receiver and speak to the remote party using the built-in transmitter. In earlier telephones, the transmitter was mounted directly on the telephone itself, which was attached to a wall at a convenient height or placed on a desk or table. Until the advent of the cordless telephone, the handset was usually wired to the base unit, typically by a flexible tinsel wire. The handset of a cordless telephone contains a radio transceiver which relays communication via a base station that is wired to the telephone line. A mobile phone does not require a base station and communicates directly with a cell site in designated frequency bands. Handset symbol A graphic symbol that designates a handset is used on cordless and mobile phones to specify placing or ending a telephone call. Usually a button with green upright (off-hook) handset icon is used for starting a call, and a red ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smartphone
A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, which facilitate wider software, internet (including web browsing over mobile broadband), and multimedia functionality (including music, video, cameras, and gaming), alongside core phone functions such as voice calls and text messaging. Smartphones typically contain a number of metal–oxide–semiconductor (MOS) integrated circuit (IC) chips, include various sensors that can be leveraged by pre-included and third-party software (such as a magnetometer, proximity sensors, barometer, gyroscope, accelerometer and more), and support wireless communications protocols (such as Bluetooth, Wi-Fi, or satellite navigation). Early smartphones were marketed primarily towards the enterprise market, attempting to bridge the functionality of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Technological Convergence
Technological convergence is the tendency for technology, technologies that were originally unrelated to become more closely integrated and even unified as they develop and advance. For example, watches, telephones, television, computers, and social media#Platform_convergence, social media platforms began as separate and mostly unrelated technologies, but have converged in many ways into an interrelated telecommunication, media, and technology industry. Definitions "Convergence is a deep integration of knowledge, tools, and all relevant activities of human activity for a common goal, to allow society to answer new questions to change the respective physical or social ecosystem. Such changes in the respective ecosystem open new trends, pathways, and opportunities in the following divergent phase of the process" (Roco 2002, Bainbridge and Roco 2016). Siddhartha Menon defines convergence as integration and digitalization. Integration, here, is defined as "a process of transformati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
