Module 3 Lesson 2.3

• ​Barcode readers are used to scan barcodes printed on various products or inventory items by decoding reflected light patterns. The barcode is linked to a database that contains more information about that product or item.

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• Biometric devices scan a person’s physical characteristics to verify their identity. These include things like finger or handprints, facial recognition, or retinal scans.

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• Cameras and camcorders allow for images and video to be transferred to a computer.

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• Digitizers and signature pads are used to transfer hand-drawn images or written signatures into a computer. Signature pads are often used to accept credit card signatures when you purchase something.

• ​Composite A single cable, with a yellow RCA connector. It carries all video information on a single cable, with the red and white cables handling audio information. Composite cables can usually run up to 20 meters (or about 65 feet) with no noticeable signal loss, but it only supports standard definition signals, and is mostly seen on older equipment.

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• Component A higher quality connection that uses three cables grouped together (with red, green, and blue RCA connectors) for analog video. Like composite, audio is carried on separate cables. You can use a component cable length of up to 10 meters (or just over 30 feet) without noticeable signal loss. Component video was popular for higher quality analog home theater equipment, but has mostly been replaced with connections like HDMI.

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• Coaxial Both audio and video are carried as a modulated radio signal through a coaxial cable with a single inner wire surrounded by an insulated layer and a braided metal shield. There are a wide variety of coaxial cables, but where displays are concerned the most common standards are the RG-59 standard used by older cable television systems, and the higher-grade RG-6 standard used by newer cable TV and broadband internet systems. Typically, they use a threaded F connector. Coaxial cables can be much longer than other copper video cables, sometimes hundreds of meters.

​MIDI stands for Musical Instrument Digital Interface, which is a protocol for recording and playing back digital music on a computer.

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MIDI-enabled devices may come in the form of a keyboard, drums, guitar, or other device that connect to a computer with a five-pin MIDI connector. Some newer devices may also use USB. The MIDI device can then be used to trigger sound samples of various instruments by physically playing the music on your device.

​Radio Frequency ID (RFID) is a means of tagging and tracking objects using specially-encoded tags. When an RFID reader scans a tag, the tag responds with the information programmed into it. A tag can either be an unpowered, passive device that only responds when scanned at close range (up to about 25m) or a powered, active device with a range of 100m. Passive RFID tags can be embedded in stickers and labels to track parcels and equipment and are used in passive proximity smart cards.

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Near Field Communications (NFC) is a peer-to-peer version of RFID; that is, an NFC device can work as both tag and reader to exchange information with other NFC devices. Near Field Communication (or NFC) is communication for devices within 20 cm, or about 18 inches of each other. The initiator's NFC chip can actively generate an RF field that powers the passive target. For additional security, the maximum range can be reduced. A distance of 4 to 5 cm (or less than 2 inches) is common. Data communication between NFC devices is two-way, secure, and can use encryption when transferring sensitive data, so it's commonly used for contactless payment systems like Apple Pay, Google Pay, and Samsung Pay, as well as for gaming applications like Disney Infinity figures and Nintendo’s Amiibo. You can even use NFC to transfer settings between two compatible smartphones or tablets, or to more quickly establish Bluetooth or WiFi connections.