Chapter 8 Flashcards
difference between a barcode and a qr code
A barcode is a one-dimensional code that stores basic information like a product ID, while a QR code is a two-dimensional code capable of holding significantly more data, such as website links or detailed product information, and can be scanned easily with a smartphone camera; essentially, barcodes are good for simple identification, while QR codes offer greater versatility for storing complex data
What is a barcode and a qr code
QR (quick response) codes and barcodes are both machine-readable, optical labels that store information about an item or product
What are floppy discs?
Plastic encased magnetic storage devices lined with a fabric that cleans off dust from its disc core. These were widely compatible with 20th century computers and were highly used from the 1970s to the 1990s until email and other message sharing applications made the transfer of files more convenient and swift in the 2000s.
What are Hard discs?
Rigid magnetic discs that utilize platters or magnetic disc surfaces spinning at high speeds. These are either built in or external extensions. Hard discs are non-volatile storage units, meaning they retain information even after the computer is powered off.
What are Flash Drives?
Flash drives are small, reliable, and portable units of storage that have integrated ICs and include flash memory and Universal Serial Bus (USB) interfaces. These can store large amounts of data permanently, and are generally more efficient with more storage capacity.
What are CDs and DVDs?
CDs (compact discs) and DVDs (Digitally Versatile Discs) are both spherical magnetized storage units that are highly common in today’s time. CDS store small bits of data while DVDs can store as much as 4.7 GBs.
What is the internet?
It is a worldwide network of computers that can access information from anywhere, anytime, including other individuals with their permission.
Who was the fax machine invented by?
Alexander Bain in 1843. It was originally referred to as the electric printing graph.
What is a computer?
an electric device operating on binary function that was primarily created as a means to perform calculations and store information. It works due to the interaction between software and hardware.
hardware are those parts that you can touch like the mouse and keyboard, the most important of which is a CPU, which has a microprocessor that is essentially the brain of the computer that translates the binary code into tangible instructions. Software is a set of commands crested by humans that direct or control the function of a computer. Operating systems are a type of software that control your computer and its connected devices.
what is modulation and demodulations?
Modulation is the process of encoding information in a transmitted signal, while demodulation is the process of extracting information from the transmitted signal.
what is an antenna?
A conductor or a system of conductors used for radiating or collecting electromagnetic energy.
Explain the flow of information through optical fibre
Optimal fibre transmits a signal encoded in light through total internal reflection, which occurs when a medium has a higher index of refraction than its surroundings. The information it transmits is converted into voltage signals which can be used to produce light.
Two types of lights are used for thid method: Light Emitting Diode (LEDs) and Injection Laser Diods (ILDs) The injection laser diodes are more efficient with greater data rates while LEDs are cheaper, reliable, and have more operational life with a greater temperature change.
Explain the flow of information through a wire
In a wire communication system, data is converted into electrical systems at the transmitter, and is then sent through wires. It is then converted back into its original form at the receiver in the end.Examples include cable television and telephone networks.
Electrical wires can be used to transmit both analogue and digital transmissions. For analogue signals, amplifiers are required every few kilo meters and for digital transmission, repeaters are required every kilo meter depending on the wire used.
Who invented the telephone/ Explain why alexander graham bell is famous?
Pioneering inventor of a simple telephone in 1876 to send voice from on place to another in the form of electrical signals. He also co-founded the American Telephone and Telegraph Company in 1885.
How is information flowed/ received
In television and cell phones, information is sent through space in the form of electromagnetic waves. In telephones, it is ent through electrical signals. Radio waves are continually reflected by the earth’s surface so they weaken over time once discharged, so microwaves are used by satellites instead, as they do not get reflected.
What is information and communication technology?
Products that process, transmit, convert, store, or receive electronic communication.
What is the differe
