Copy of IGCSE COMPUTER SCIENCE

Personal assistant

________ (vectors) is controlled by microprocessor and use cloud connectivity to connect to the internet.

HDD

________ have very slow data access compared to RAM.

Interception

________ can be carried out using a packet sniffer, which examines data packets being sent over a network.

HTML files

________ are sent from the website server to the computer.

Input devices

________, usually sensors, send data readings to the microprocessor (computer) at set intervals.

Email

________ and texts can be sent simply by rerouting packets.

Unicode

________ use either 8, 16, 32 bits per character, so it can represent characters from languages from around the world.

Media Access Control

________ address: unique number that identifies the device that is connected to the network or internet, usually made of 48 bits.

Von Neumann architecture

________ is based- on stored program concepts.

Thrash point

________ is achieved when most processes come to a stop because the computer is too busy dealing with virtual memory paging (moving data in and out of memory)

Physical servers

________ and storage are needed to store data in cloud storage and it owns by a hosting company.

Optical Character Recognition

________ (OCR) is a software which converts scanned documents into a text file format.

Bandwidth

________: the amount of data that can be transmitted in one time.

Actuators

________ are used to operate the steering track, brakes and throttles under control of the computer.

Hexadecimal

________ is easier for humans to understand than binary, as it is a shorter representation of the binary.

Firewall

________ can keep a list of all undesirable IP addresses.

illegal access

The act of gaining ________ to a computer system without the users permission.

electric field

When ________ is applied to electrodes, they give off light-> no forming of backlighting.

typical features

Rules- look for ________ which are associated with spyware, identify potential security threats.

laser light

Wavelength of ________ is less than CD and DVD (stores up to five times more data than DVD)

Serial transmission

________: bits are sent sequentially (one after the other) down the same wire (channel)

diodes

Light emitting ________, the display is made up of pixels that are arranged together as a matrix.

negative acknowledgement

A(n) ________ means that the data was received but it can not be used as it failed an error check.

CMOS

________ generates electric pulses to represent the reflected red light and these pulses are sent to a digital signal processor (DSP)

barcode

The ________ is read by a red light or laser (light emitting diode)

Router

________: a device that enables data packets to be moved between different networks, for example, to join a LAN to a WAN.

Structure diagrams

________ can be used to show top- down design in a diagrammatic form.

USB

________: a type of cable and connector commonly used for half- duplex or full- duplex serial data transmission between a computer and attached devices.

Trojan horse

A(n) ________ replaces all or part of the legitimate software with the intent of carrying out some harm to the users computer system.

NIC

________: a hardware component (circuit board or chip) that is required to allow a device to connect to a network, such as the internet, it contains MAC.

current instruction

Registers: program counter (PC), memory address register (MAR), memory data register (MDR), ________ register (CIR) and accumulator (ACC)

Blockchain

________ can be used in voting records, medical records, land records, smart contracts,

IP

________: location of devices; MAC: actual devices at location of devices.

DLP

The number of micro mirrors and the way they are arranged on the ________ chip determines the resolution of the image.

ADC

________ converts electrical charges to level of brightness, more pixels means higher quality.

CCFL

________ uses two fluorescent tubes behind the LCD screen which supplies the light source.

Satellite TV transmission

________ are encrypted to prevent users who are not subscribed to the platform.

Human operator

________ will carry out the tasks manually and robot knows how to carry the task.

Autonomous grass cutter

________ (mowers) uses proximity sensor and camera to avoid obstacle and cover the whole room quickly.

Scanners

________ take images at several points, x, y and z (lasers, magnetic, white light)

Cameras

________ catch visual data from the surroundings, while radar and ultrasonics allow the vehicle to build up a 3D image of its surrounding.

Autonomous vacuum

________ cleaner uses proximity sensor and camera to avoid obstacle and cover the whole room quickly.

Inductive reasoning

________: ability to draw reasoned conclusions based on given data /situations.

Drones

________ can also be used in cloud seeding where the ________ can add silver iodide crystals to a cloud forcing it to give up its rainwate.

Machine learning

________ is when a program has the ability to automatically adapt its own processes and /or data:

Encryption keys

________ are created by supplying a message or key to the hashing algorithm which turns it into a string of characters usually shown in hexadecimal.

Media Access Control address

unique number that identifies the device that is connected to the network or internet, usually made of 48 bits

Character sets

Made of letters, numbers and various symbol, that can be encoded in a computer as patterns of binary digit

ASCII code

7 bit codes that represent the letters, number and characters found on standard keyboards together with 32 control codes

Choose shortest possible paths

this may not always be the shortest path could be taken, since certain paths may be too busy or not suitable

Bandwidth

the amount of data that can be transmitted in one time

Serial transmission

bits are sent sequentially (one after the other) down the same wire (channel)

USB

a type of cable and connector commonly used for half-duplex or full-duplex serial data transmission between a computer and attached devices

parity check (odd and even), checksum and echo check

Describe the processes involved in each of the following error detection methods for detecting errors in data after transmission

Parity check

An extra bit (parity bit) added to a string of binary code to ensure the number of 1-bits are either even or odd, depending upon the parity check system used

Registers

program counter (PC), memory address register (MAR), memory data register (MDR), current instruction register (CIR) and accumulator (ACC)

NIC

a hardware component (circuit board or chip) that is required to allow a device to connect to a network, such as the internet, it contains MAC

Media Access Control address

unique number that identifies the device that is connected to the network or internet, usually made of 48 bits

Router

a device that enables data packets to be moved between different networks, for example, to join a LAN to a WAN

Managing files

a file system is created to organise files and directories, which gives programs a consistent way to store and retrieve information

Software interrupts

an attempt to divide by zero, 2 processes trying to access the same memory location

Assembly language

low-level language that is used for developing code for specialist hardware, e.g