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Mobile phone

A mobile phone or cell phone[a] is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area, as opposed to a fixed-location phone (landline phone). 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 cellphones (or "cell phones") in North America. In addition to telephony, digital mobile phones support a variety of other services, such as text messaging, multimedia messaging, email, Internet access (via LTE, 5G NR or Wi-Fi), short-range wireless communications (infrared, Bluetooth), satellite access (navigation, messaging connectivity), business applications, payments (via NFC), multimedia playback and streaming (radio, television), digital photography, and video games. Mobile phones offering only basic capabilities are known as feature phones (slang: "dumbphones"); mobile phones that offer greatly advanced computing capabilities are referred to as smartphones.[1]

For the modern mobile phone, see Smartphone.

The first handheld mobile phone was demonstrated by Martin Cooper of Motorola in New York City on 3 April 1973, using a handset weighing c. 2 kilograms (4.4 lbs).[2] In 1979, Nippon Telegraph and Telephone (NTT) launched the world's first cellular network in Japan.[3] In 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to over seven billion; enough to provide one for every person on Earth.[4] In the first quarter of 2016, the top smartphone developers worldwide were Samsung, Apple and Huawei; smartphone sales represented 78 percent of total mobile phone sales.[5] For feature phones as of 2016, the top-selling brands were Samsung, Nokia and Alcatel.[6]


Mobile phones are considered an important human invention as they have been one of the most widely used and sold pieces of consumer technology.[7] The growth in popularity has been rapid in some places, for example, in the UK, the total number of mobile phones overtook the number of houses in 1999.[8] Today, mobile phones are globally ubiquitous,[9] and in almost half the world's countries, over 90% of the population owns at least one.[10]

A (CPU), the processor of phones. The CPU is a microprocessor fabricated on a metal–oxide–semiconductor (MOS) integrated circuit (IC) chip.

central processing unit

A , providing the power source for the phone functions. A modern handset typically uses a lithium-ion battery (LIB), whereas older handsets used nickel–metal hydride (Ni–MH) batteries.

battery

An input mechanism to allow the user to interact with the phone. These are a for feature phones, and touch screens for most smartphones (typically with capacitive sensing).

keypad

A which echoes the user's typing, and displays text messages, contacts, and more. The display is typically either a liquid-crystal display (LCD) or organic light-emitting diode (OLED) display.

display

for sound.

Speakers

(SIM) cards and removable user identity module (R-UIM) cards.

Subscriber identity module

A hardware on some phones

notification LED

A study by found that one in ten mobile phone subscribers have a second phone that is often kept secret from other family members. These phones may be used to engage in such activities as extramarital affairs or clandestine business dealings.[43]

Motorola

Some organizations assist victims of domestic violence by providing mobile phones for use in emergencies. These are often refurbished phones.

[44]

The advent of widespread text-messaging has resulted in the , the first literary genre to emerge from the cellular age, via text messaging to a website that collects the novels as a whole.[45]

cell phone novel

also facilitates activism and citizen journalism.

Mobile telephony

The reported that mobile phones have spread faster than any other form of technology and can improve the livelihood of the poorest people in developing countries, by providing access to information in places where landlines or the Internet are not available, especially in the least developed countries. Use of mobile phones also spawns a wealth of micro-enterprises, by providing such work as selling airtime on the streets and repairing or refurbishing handsets.[46]

United Nations

In and other African countries, people used to travel from village to village to let friends and relatives know about weddings, births, and other events. This can now be avoided in areas with mobile phone coverage, which are usually more extensive than areas with just land-line penetration.

Mali

The TV industry has recently started using mobile phones to drive live TV viewing through mobile apps, advertising, , and mobile TV.[47] It is estimated that 86% of Americans use their mobile phone while watching TV.

social TV

In some parts of the world, mobile phone sharing is common. Cell phone sharing is prevalent in urban India, as families and groups of friends often share one or more mobile phones among their members. There are obvious economic benefits, but often familial customs and traditional gender roles play a part. It is common for a village to have access to only one mobile phone, perhaps owned by a teacher or missionary, which is available to all members of the village for necessary calls.[49]

[48]

Smartphones also have the use for individuals who suffer from diabetes. There are apps for patients with diabetes to self monitor their blood sugar, and can sync with flash monitors. The apps have a feature to send automated feedback or possible warnings to other family members or healthcare providers in the case of an emergency.

at HowStuffWorks

"How Cell Phones Work"

15 photos with captions from Time magazine

"The Long Odyssey of the Cell Phone"

– a video documentary by the Canadian Broadcasting Corporation

Cell Phone, the ring heard around the world