Hardware terms explain

Access Point

An access point is a device, such as a wireless router, that allows wireless devices to connect to a network. Most access points have built-in routers, while others must be connected to a router in order to provide network access. In either case, access points are typically hardwired to other devices, such as network switches or broadband modems.

Access points can be found in many places, including houses, businesses,
and public locations. In most houses, the access point is a wireless router, which is connected to a DSL or cable modem. However, some modems may include wireless capabilities, making the modem itself the access point. Large businesses often provide several access points, which allows employees to wirelessly connect to a central network from a wide range of locations. Public access points can be found in stores, coffee shops, restaurants, libraries, and other locations. Some cities provide public access points in the form of wireless transmitters that are connected to streetlights, signs, and other public objects.

While access points typically provide wireless access to the Internet, some are intended only to provide access to a closed network. For example, a business may provide secure access points to its employees so they can wirelessly access files from a network server. Also, most access points provide Wi-Fi access, but it is possible for an access point to refer to a Bluetooth device or other type of wireless connection. However, the purpose of most access points is to provide Internet access to connected users.

The term "access point" is often used synonymously with base station, though base stations are technically only Wi-Fi devices. It may also be abbreviated AP or WAP (for wireless access point). However, WAP is not as commonly used as AP since WAP is the standard acronym for Wireless Access Protocol.

Adapter

An adapter is a device that allows a specific type of hardware to work with another device that would otherwise be incompatible. Examples of adapters include electrical adapters, video adapters, audio adapters, and network adapters.

An electrical adapter, for instance, may convert the incoming voltage from 120V to 12V, which is suitable for a radio or other small electronic device. Without regulating voltage through an adapter, the incoming electrical surge could literally fry the internal components of the device. Most consumer electronics have adapters attached to the plug at the end of the electrical cord. Whenever you see an plug surrounded by a large box, it is most likely an electrical adapter. You can typically find the input and output voltage printed directly on the adapter. A device that does not have an adapter on the end of its electrical cable typically has a built-in voltage adapter. For example, desktop computers typically have the adapter built into the internal power supply.

Video adapters and audio adapters adapt one type of interface to another type of connector. For example, a DVI to VGA adapter allows you to connect theDVI output of a laptop to the VGA input of a projector. Most professional audio devices use 1/4" audio jacks, while most computers have 1/8" "minijacks" for audio input and output. Therefore, 1/4" to 1/8" audio adapters are often used to import audio into computers. Likewise, an 1/8" to 1/4" adapter can used to output audio from a computer to a professional audio system. Since a large number of audio and video interfaces exist, there are hundreds of audio and video adapters available.

Network cards, or NICs, are also called network adapters. These include Ethernet cards, internal Wi-Fi chips, and external wireless transmitters. While these devices don't convert connections like audio or video adapters, they enable computers to connect to network. Since the network card makes it possible to connect to an otherwise incompatible network, the card serves as an adapter. Similarly, video cards are sometimes called video adapters because they convert a video signal to an image that can be displayed on a monitor.

ADSL (Asymmetric Digital Subscriber Line)

Stands for "Asymmetric Digital Subscriber Line." ADSL is a type of DSL, which is a method of transferring data over copper telephone lines. While symmetrical DSL (SDSL) uploads and downloads data at the same speed, ADSL has different maximum data transfer rates for uploading and downloading data.

For example, an ADSL connection may allow download rates of 1.5Mbps, while upload speeds may only reach 256Kbps. Since most users download much more data than they upload, this difference usually does not make a noticeable impact on Internet access speeds. However, for Web servers or other computers that send a lot of data upstream, ADSL would be an inefficient choice.

ADC (Analog-to-Digital Converter)

Stands for "Analog-to-Digital Converter." Since computers only process digital information, they require digital input. Therefore, if an analog input is sent to a computer, an analog-to-digital converter (ADC) is required. This device can take an analog signal, such as an electrical current, and digitize it into a binary format that the computer can understand.

A common use for an ADC is to convert analog video to a digital format. For example, video recorded on 8mm film or a VHS tape is stored in an analog format. In order to transfer the video to a computer, the video must be converted to a digital format. This can be done using an ADC video conversion box, which typically has composite video inputs and a Firewire output. Some digital camcorders that have analog inputs can also be used to convert video from analog to digital.

ADCs may also be used to convert analog audio streams. For example, if you want to record sounds from a microphone, the audio must be converted from the microphone's analog signal into a digital signal that the computer can understand. This is why all sound cards that have an analog audio input also require an ADC that converts the incoming audio signal to a digital format. The accuracy of the audio conversion depends on the sampling rate used in the conversion process. Higher sampling rates provide a better estimation of the analog signal, and therefore produce a higher-quality sound.

While ADCs convert analog inputs into a digital format that computers can recognize, sometimes a computer must output an analog signal. For this type of conversion, a digital-to-analog converter (DAC) is used.

NOTE: ADC can also stand for "Apple Display Connector," which was a proprietary video connector developed by Apple. It combined DVI, USB, and AC power into a single cable. Apple stopped producing computers with ADC ports in 2004 in favor of the standard DVI connection.