PDA的英文简介

PDA的英文简介
PDA的英文简介

PDA的英文简介
PDA
PDA是Personal Digital Assistant的缩写,字面意思是“个人数字助理”.这种手持设备集中了计算,电话,传真,和网络等多种功能.
PDA一般都不配备键盘,而用手写输入或语音输入.以上所说的是广义的PDA.

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PDA
A personal digital assistant (PDA) is a handheld computer also known as palmtop computers. Newer PDAs also have both color screens and audio capabilities, enabling...

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PDA
A personal digital assistant (PDA) is a handheld computer also known as palmtop computers. Newer PDAs also have both color screens and audio capabilities, enabling them to be used as mobile phones, (smartphones), web browsers, or portable media players. Many PDAs can access the Internet, intranets or extranets via Wi-Fi, or Wireless Wide-Area Networks (WWANs). Many PDAs employ touch screen technology.
The first PDA is considered to be the CASIO PF-3000 released in May 1983. GO Corp. was also pioneering in the field. The term was first used on January 7, 1992 by Apple Computer CEO John Sculley at the Consumer Electronics Show in Las Vegas, Nevada, referring to the Apple Newton.
Currently, a typical PDA has a touch screen for entering data, a memory card slot for data storage and at least one of the following for connectivity: IrDA, Bluetooth and/or WiFi. However, many PDAs (typically those used primarily as telephones) may not have a touch screen, using softkeys, a directional pad and either the numeric keypad or a thumb keyboard for input.
Software typically required to be a PDA includes an appointment calendar, a to-do list, an address book for contacts and some sort of note program. Connected PDAs also typically include E-mail and Web support.
Many original PDAs, such as the Apple Newton and Palm Pilot, featured touch screens for user interaction, having only a few buttons usually reserved for shortcuts to often used programs. Touch screen PDAs, including Windows Pocket PC devices, usually have a detachable stylus that can be used on the touch screen. Interaction is then done by tapping the screen to activate buttons or menu choices, and dragging the stylus to, for example, highlight. Text input is usually done in one of four ways:
• Using a virtual keyboard, where a keyboard is shown on the touch screen. Input is done by tapping letters on the screen.
• Using external keyboard or chorded keyboard connected by USB, IR or Bluetooth.
• Using letter or word recognition, where letters or words are written on the touch screen, and then "translated" to letters in the currently activated text field. Despite rigorous research and development projects, end-users experience mixed results with this input method, with some finding it frustrating and inaccurate, while others are satisfied with the quality.[1] Recognition and computation of handwritten horizontal and vertical formulas such as "1 + 2 =" was also under development.
• Stroke recognition (termed Graffiti by Palm). In this system a predefined set of strokes represents the various characters needed. The user learns to draw these strokes on the screen or in an input area. The strokes are often simplified character shapes to make them easier to remember.
PDAs for business use, including the BlackBerry and Treo, have full keyboards and scroll wheels or thumb wheels to facilitate data entry and navigation, in addition to supporting touch-screen input. There are also full-size foldable keyboards available that plug directly, or use wireless technology to interface with the PDA and allow for normal typing. BlackBerry has additional functionality, such as push-based email and applications.
Newer PDAs, such as the Apple iPhone and iPod touch include new user interfaces using other means of input. The iPhone and iPod touch uses a technology called Multi-touch.
Although many early PDAs did not have memory card slots now most have either an SD (Secure Digital) and/or a Compact Flash slot. Although originally designed for memory, SDIO and Compact Flash cards are available for such things as Wi-Fi and Webcams. Some PDAs also have a USB port, mainly for USB flash drives. Some PDAs are now compatible with micro SD cards, wich are physically much smaller than standard SD cards.
While many earlier PDAs connected via serial ports or other proprietary format, many today connect via USB cable. This served primarily to connect to a computer, and few, if any PDAs were able to connect to each other out of the box using cables, as USB requires one machine to act as a host - functionality which was not often planned. Some PDAs were able to connect to the internet, either by means of one of these cables, or by using an extension card with an ethernet port/RJ-45 adaptor.and ALSO
Most modern PDAs have Bluetooth wireless connectivity, an increasingly popular tool for mobile devices. It can be used to connect keyboards, headsets, GPS and many other accessories, as well as sending files between PDAs. Many mid-range and superior PDAs have Wi-Fi/WLAN/802.11-connectivity, used for connecting to Wi-Fi hotspots or wireless networks. Older PDAs predominantly have an IrDA (infrared) port; however fewer current models have the technology, as it is slowly being phased out due to support for Bluetooth and Wi-Fi. IrDA allows communication between two PDAs: a PDA and any device with an IrDA port or adapter. Most universal PDA keyboards use infrared technology because many older PDAs have it, and infrared technology is low-cost and has the advantage of being permitted aboard aircraft.
An important function of PDAs is synchronizing data with a PC. This allows up-to-date contact information stored on software such as Microsoft Outlook or ACT! to update the database on the PDA. The data synchronization ensures that the PDA has an accurate list of contacts, appointments and e-mail, allowing users to access the same information on the PDA as the host computer.
The synchronizing also prevents the loss of information stored on the device in case it is lost, stolen, or destroyed. Another advantage is that data input is usually a lot quicker on a PC, since text input via a touch screen is still not quite optimal. Transferring data to a PDA via the computer is therefore a lot quicker than having to manually input all data on the handheld device.
Most PDAs come with the ability to synchronize to a PC. This is done through synchronization software provided with the handheld, such as HotSync Manager, which comes with Palm OS handhelds, Microsoft ActiveSync for older versions of Windows or Windows Mobile Device Center on Windows Vista, which comes with Windows Mobile handhelds.
These programs allow the PDA to be synchronized with a Personal information manager. This personal information manager may be an outside program or a proprietary program. For example, the BlackBerry PDA comes with the Desktop Manager program which can synchronize to both Microsoft Outlook and ACT!. Other PDAs come only with their own proprietary software. For example, some early Palm OS PDAs came only with Palm Desktop while later Palms such as the Treo 650 has the built-in ability to sync to Palm Desktop and/or Microsoft Outlook, while Microsoft's ActiveSync and Windows Mobile Device Center only synchronize with Microsoft Outlook or a Microsoft Exchange server.
Third-party synchronization software is also available for many PDAs from companies like Intellisync and CompanionLink. This software synchronizes these handhelds to other personal information managers which are not supported by the PDA manufacturers, such as GoldMine and Lotus Notes.
PDAs offer varying degrees of accessibility for people with differing abilities, based on the particular device and service. People with vision, hearing, mobility, and speech impairments may be able to use PDAs on a limited basis, and this may be enhanced by the addition of accessibility software (e.g. speech recognition for verbal input instead of manual input). Universal design is relevant to PDAs as well as other technology, and a viable solution for many user-access issues, though it has yet to be consistently integrated into the design of popular consumer PDA devices.
PDAs have recently become quite useful in the Traumatic Brain Injury/Posttraumatic Stress Disorder population, especially seen in troops returning home from Operation Iraqi Freedom(OIF)/Operation Enduring Freedom(OEF). PDAs address memory issues and help these men and women out with daily life organization and reminders. As of quite recently, the Department of Veterans' Affairs (VA) has begun issuing thousands of PDAs to troops who present the need for them. Occupational therapists have taken on a crucial role within this population helping these veterans return to the normalcy of life they once had.

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