Input, Output and Storage

What is an input device?

A device used to enter data into a computer.

What is an output device?

A device used to present information from a computer.

What is a keyboard used for?

Entering text and commands into a computer.

What is a webcam used for?

Capturing photos and videos as input.

What is a magnetic stripe reader used for?

Reading data stored on the magnetic stripe of a card.

What is a barcode reader used for?

Reading barcodes to enter product or item information.

What are speakers used for?

Outputting sound.

What is a printer used for?

Producing a hard copy of information on paper.

What is a projector used for?

Displaying images or videos on a large screen.

Why is a touchscreen both an input and output device?

It displays information and detects touch input.

What factors should be considered when choosing an input or output device?

Suitability for the task, speed, accuracy and cost.

Why is a barcode reader suitable for a supermarket checkout?

It enters product information quickly and accurately without typing it manually.

Why might a projector be suitable for a classroom?

It displays information on a large screen so many people can see it.

Give an example of an input device in a fitness tracker and its use.

A heart-rate sensor measures the wearer's heart rate.

What is secondary storage used for?

Storing data and programs long term, even when the power is off.

What are the three main types of secondary storage

Magnetic, optical and flash storage.

How does optical storage store and read data?

Data is stored as patterns on a disc and read using a laser.

Give examples and uses of optical storage.

CDs for music; DVDs for films; Blu-ray discs for high-resolution films.

What are the advantages of optical storage?

Discs are portable, lightweight and inexpensive to distribute.

What are the disadvantages of optical storage?

Limited capacity, relatively slow access and can be damaged by scratches.

What is the difference between CD-ROM, CD-R and CD-RW?

CD-ROM is read-only; CD-R can be written to once; CD-RW can be rewritten.

How does magnetic storage store data?

It stores data as different magnetic states that represent binary values.

Give two examples of magnetic storage.

Hard disk drives (HDDs) and magnetic tape.

How does a hard disk drive (HDD) work?

A read/write head accesses data stored magnetically on rotating platters.

What are the advantages of an HDD?

High storage capacity and low cost per GB.

What are the disadvantages of an HDD?

Moving parts can be damaged by knocks, and access is usually slower than an SSD.

Why is magnetic tape useful for backups and archives?

It can store large amounts of data cheaply, but accessing individual files is slow.

How does flash storage store data?

It stores electrical charge in memory cells to represent binary values.

Is flash storage volatile or non-volatile?

Non-volatile. It keeps its data when the power is switched off.

Give three examples of flash storage devices.

Solid state drives (SSDs), USB flash drives and memory cards.

What are the advantages of flash storage?

Fast access, small size, low power use and no moving parts.

What are the disadvantages of flash storage?

Higher cost per GB than HDDs and a limited number of write cycles.

Why is an SSD suitable for a laptop that is often moved?

It has no moving parts, so it is less likely to be damaged by movement; it also has fast access speeds.

Compare HDDs and SSDs.

HDDs are usually cheaper per GB and have moving parts. SSDs are usually faster, more durable and use less power.

Why is flash storage suitable for a wearable fitness tracker?

It is small, uses little power, has no moving parts and can record data quickly.

What factors matter when choosing a storage device?

Capacity, speed, cost, size, durability, power use and the intended use.

What does RAM stand for and what is its purpose?

Random Access Memory. It holds the data and instructions currently being used by running programs.

What does ROM stand for and what is its purpose?

Read Only Memory. It stores firmware or startup instructions that must be kept when power is off.

What does volatile memory mean?

Memory that loses its contents when power is switched off.

What does non-volatile memory mean?

Memory that keeps its contents when power is switched off.

Compare RAM and ROM.

RAM is volatile and can be read from and written to while programs run. ROM is non-volatile and normally stores instructions that are not changed in regular use.

Why is RAM used instead of secondary storage for running programs?

RAM allows the CPU to access the data and instructions currently needed much faster.

Why does a computer need ROM when it starts?

ROM keeps the startup instructions or firmware available even when the computer was switched off.

How might RAM and ROM be used in an embedded system?

RAM holds data being processed; ROM stores the firmware used to control the device.

What is virtual storage

Storage that may appear local but is physically stored elsewhere on a network or in the cloud.

Give two examples of virtual storage.

Cloud storage such as Google Drive or OneDrive, and shared network storage.

How does virtual storage work?

Files are stored on remote physical drives and accessed through a network, sometimes with several drives appearing as one storage space.

Why might a person or organisation need virtual storage?

To access and share files from different devices or locations without keeping every file on each device.

What are the advantages of virtual storage?

Files can be accessed remotely, shared easily and used across different devices.

What are the disadvantages of virtual storage?

Access depends on the network speed and availability, and storage may have ongoing costs.

Why might a school use shared network storage?

Students and staff can access their files from different computers on the school network.