The first telephones were directly connected to each other from one customer's office or residence to another customer's location. Being impractical beyond just a few customers, these systems were quickly replaced by manually operated centrally located switchboards. These exchanges were soon connected together, eventually forming an automated, worldwide public switched telephone network. For greater mobility, various radio systems were developed for transmission between mobile stations on ships and automobiles in the mid-20th century. Hand-held mobile phones were introduced for personal service starting in 1973. In later decades, their analog cellular system evolved into digital networks with greater capability and lower cost.
disadvantages of mobile phones essay in urdu
Convergence in communication services has provided a broad spectrum of capabilities in cell phones, including mobile computing, giving rise to the smartphone, the dominant type of telephone in the world today.
Mobile phones require a SIM card to be inserted into the phone. The SIM card is a small PVC card containing a small integrated circuit which stores the user's international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers to the cellular network.
Mobile phones generally incorporate an LCD or OLED display, with some types, such as smartphones, having touch screens. Since the 1990s, mobile phones have gained other features which are not directly related to their primary function as telephones. These include text messaging, calendars, alarm clocks, personal schedulers, cameras, music players, games and later, internet access and smartphone functionality. Nearly all mobile phones have the ability to send text messages to other users via the SMS (Short Message Service) protocol. The multimedia messaging service (MMS) protocol enables users to send and receive multimedia content, such as photos, audio files and video files. As their functionality has increased over the years, many types of mobile phone, notably smartphones, require an operating system to run. Popular mobile phone operating systems in the past have included Symbian, Palm OS, BlackBerry OS and mobile phone versions of Windows. As of 2022, the most used operating systems are Google's Android and Apple's iOS.[31]
Before the era of smartphones, mobile phones were generally manufactured by companies specializing in telecommunications equipment, such as Nokia, Motorola, and Ericsson. Since the advent of smartphones, mobile phone manufacturers have also included consumer electronics companies, such as Apple, Samsung and Xiaomi.
In 2002, only 10% of the world's population used mobile phones and by 2005 that percentage had risen to 46%.[32] By the end of 2009, there were a total of nearly 6 billion mobile and fixed-line telephone subscribers worldwide. This included 1.26 billion fixed-line subscribers and 4.6 billion mobile subscribers.[33]
As of 2022, most mobile phones are smartphones, being a combination of a mobile phone and a personal computing device in the same unit. Most smartphones are primarily operated using a graphical user interface and a touch screen. Many phones have a secondary voice user interface, such as Siri on Apple iPhones, which can operate many of the device's functions, as well as enabling users to use spoken commands to interact with the internet. Typically alphanumeric text input is accomplished via an on-screen virtual keyboard, although some smartphones have a small physical keyboard. Smartphones offer the ability to access internet data through the cellular network and via wi-fi, and usually allow direct connectivity to other devices via Bluetooth or a wired interface, such as USB or Lightning connectors. Smartphones, being able to run apps, have vastly expanded functionality compared to previous mobile phones. Having internet access and built in cameras, smartphones have made video calling readily accessible via IP connections. Smartphones also have access to a large number of web services and web apps, giving them functionality similar to traditional computers, although smartphones are often limited by their relatively small screen size and the size of their keyboards. Typically, smartphones feature such tools as cameras, media players, web browsers, email clients, interactive maps, satellite navigation and a variety of sensors, such as a compass, accelerometers and GPS receivers. In addition to voice calls, smartphone users commonly communicate using a wide variety of messaging formats, including SMS, MMS, email, and various proprietary messaging services, such as iMessage and various social media platforms.
A satellite telephone, or satphone, is a type of mobile phone that connects to other phones or the telephone network by radio link through satellites orbiting the Earth instead of terrestrial cell sites, as cellphones do. Therefore, they can work in most geographic locations on the Earth's surface, as long as open sky and the line-of-sight between the phone and the satellite is provided. Depending on the architecture of a particular system, coverage may include the entire Earth or only specific regions. Satellite phones provide similar functionality to terrestrial mobile telephones; voice calling, text messaging, and low-bandwidth Internet access are supported through most systems. The advantage of a satellite phone is that it can be used in such regions where local terrestrial communication infrastructures, such as landline and cellular networks, are not available.
Essay on Disadvantage of Mobile Phones: In the modern world of science and technology, we all face different problems while using technologies. The mobile phone is a product of science which has become very important for us. Thus most of us use mobile phones like these are our friends, and that causes various problems. There are so many disadvantages of using mobile phones. Constant distraction, social disruption, never-ending workdays, ongoing expenses, cause of accidents, health problems, youth crimes, etc. are some of the major disadvantages of using mobile phones.
Mobile phones leave negative impacts on personal contacts. We have seen many teenagers having dinner with their family members. But instead of joining in conversations with them, they keep themselves busy on their mobile phones scrolling through news feeds on social media applications. In this way, many people have lost their conversation skills which restrict them from interacting with other people. Using cell phones can cause distance in relationships too.
There are so many people in this world who use mobiles phones as fashion. They upgrade the models of mobile phones they use regularly. Mobile phones are costly nowadays, and buying new models in a certain interval of time will make you spend too much money.
Mobile phones contain so many private photos and videos. Maintaining the privacy of these photos and videos have become harder these days as the mobile manufacturing companies and applications installed in the phones can go through your things in your phones. Hackers can easily hack your mobile, and the private things in your phone can be easily stolen.
When we use mobile phones constantly, we get addicted to mobiles phones. Addiction to mobile phones can cause various mental disorders to human bodies. Isolation in the people is caused due to excessive usage of mobile phones.
Mobile phones are one of the main reasons behind the wastage of our valuable times. Mostly the students of school, colleges and teenagers are affected by wastage of time due to over usage of mobile phones. They spend too much time using mobile phones for playing video games, chatting, watching movies, and thus they waste their precious time.
1. Mobile phones cause isolation in people. 2. Excessive usage of mobile phones causes wastage of valuable time. 3. Addiction to mobile phones causes distraction from works. 4. Wastage of too much money is also caused due to mobile phones. 5. Mobile phones cause cyberbullying. 6. There are many security issues in mobile phones that can leak the private info and photos or videos on the phone. 7. People lose time for their study due to overusing mobile phones. 8. Distance from relatives and family members is one of the few negative impacts of mobile phones. 9. Mobile phones cause various health problems and sleeping issues, 10. Cell phones are one of the main reasons for road accidents.
Because exposure to the radiofrequency (RF) fields emitted bymobile phones is generally more than a 1000 times higher than from basestations, and the greater likelihood of any adverse effect being due tohandsets, research has almost exclusively been conducted on possibleeffects of mobile phone exposure.
Scientists have reported other health effects of using mobilephones including changes in brain activity, reaction times, and sleeppatterns. These effects are minor and have no apparent healthsignificance. More studies are underway to try to confirm thesefindings.
When mobile phones are used very close to some medical devices(including pacemakers, implantable defibrillators, and certain hearingaids) there is the possibility of causing interference with theiroperation. The risk is much reduced for 3G phones and newer equipment.There is also the potential of interference between mobile phonessignals and aircraft electronics. Some countries have licensed mobilephone use on aircraft during flight using systems that control the phoneoutput power.
Research has shown an increased risk of traffic accidents,some 3-4 times greater chance of an accident, when mobile phones (eitherhandheld or with a "hands-free" kit) are used while driving due todistraction.
While an increased risk of brain tumours from the use ofmobile phones is not established, the increasing use of mobile phonesand the lack of data for mobile phone use over time periods longer than15 years warrant further research of mobile phone use and brain cancerrisk. In particular, with the recent popularity of mobile phone useamong younger people, and therefore a potentially longer lifetime ofexposure, WHO has promoted further research on this group and iscurrently assessing the health impact of RF fields on all studiedendpoints. 2ff7e9595c
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