Karteikarten
Computer Studies
Karten in diesem Stapel (113)
- 1What is an algorithm?It is a set of instructions independent of any programming language which solves problems or calculates a function.
- 2What are the standard constructs of an algorithm?-Sequence
-Assignment
-Selection
-Repetition - 3What is a sequence?It means performing an operation each steps consecutively in the order they occur.
- 4What is an assignment?It means giving a value to a variable.
- 5What is a selection?It means to choose a step or to a take a decision.
- 6What is a repetition?It is a sequence of steps which loop until a requirement is met.
- 7What are the different kind of loops?Do...While Loop
While...Do Loop
Repeat...Until Loop
For Loop - 8What is a pseudocode?A pseudocode uses a combination of programming terminology and plain english to describe algorithms in a form which is easier for people to understand than real programming language code.
- 9What is visual basic(VB) ?VB has very simple programming syntax and it is not case sensitive.
- 10What is a concatonation?This means to add pieces of text(strings) together.
- 11Strings can be manipulated in various ways:- It can be formatted.
- It can be made all in uppercase.
- Spaces can be removed.
- The length of the strings can be counted. - 12stages of problem solving:1. Understand the problem.
2. Define the problem.
3. Defining the bounderies.
4. Planning the solution.
5. Check the solution. - 13What are structure charts?It is a chart which shows the breakdown of a system into its lowest manageable task.
- 14What is an array?An array is set of values which are logically related to each other.
- 15Error types in programming:- Compilation error (syntax error)
- Run-time error
- Logic error (semantic error) - 16What is a top down approach?A top down approach also known as a stepwise design is the breaking down of a system into subsystems.
- 17Procedures and function?Procedures and functions allow us to save lots of lines of codes. They allow codes to be reused, to structure programming, easily incooperate other people's code.
- 18Difference between a procedure and a function?Procedures do not return any value whereas function must return a value.
- 19What are calls?Calls allow you to run the code declared in a procedure or function.
- 20What is SQL?SQL stands for structured query or standard query language. It lets you access and manipulate databases.
- 21RDBMS?Relational database management system.
- 22What is an operating system?An os is designed to run the background of a computer system and provides an environment in which application software can be executed.
- 23What are the purposes of an operating system?- The os must manage the physical resources of the computer.
- The os provides mean of communication between the user and the computer.
- The os provides a platform in which the application software can run.
- The os maintain security.
- The os hides the complexity of the hardware from the user. - 24What is a batch processing?A batch processing does not allow interaction between the user and the processor during the execution of a program and lots of programs are collected together to form a batch.
- 25Why is batch processing used?- There are large amounts of data to be processed.
- The data are very similar in nature and require similar processing.
- The computer system has identifiable time when it is not being used and so has available processing time.
- The application does not require interaction by the user. - 26Examples of batch processing?- Processing in payroll.
- The production of bank statements for customer at periodic intervals.
- The production of utility bills. - 27What is real time processing?In real time processing, the processing can be quickly enough to affect the next input for process that needs to be carried out.
- 28What are the two standardised codes used internationally for character representation of data?ascii - american stadard code for information interchange.
EBCDIC - Extended binary coded decimal interchange code. - 29Byte?A byte holds one character.
- 30What are different number system?- Denary number system.
- Binary number system.
- Hexadecimal number system. - 31What is a denary?It is a number system consisting of digits from 0 - 9 used to represent numbers either singly or in ordered group.
- 32What is an unsigned integer?An unsigned integer is a whole number whose sign( + , - ) is not represented in the word.
- 33What is a hardware?Hardware refer to the physical electronic and electrical components that make up a computer system.
- 34What are peripheral devices?Peripheral devices are hardware that are outside of the CPU and connected to the computer by internal wiring, cables or wireless technology.
- 35What is a software?A software is a set of instructions that makes the computer hardware usable.
- 36Types of software?- System software.
- Application software. - 37What is a single user OS?A single user os controls a system which has only one use and their programs at any time.
- 38What is multi-user os?A multi-user os has a single powerful computer which is connected to a umber of terminals.
- 39What is a multi-tasking os?A multi-tasking os allows several application to be available simultaneously.
- 40What is network?A network comprises of several computer linked together for the purpose of communications and sharing of resources.
- 41A network os carry out task such as?- control access to the network.
- Management of the filling system.
- Management of all application programs from the server.
- Management of all shared peripherals. - 42what is a bitmap graphic?It is a collection of pixels from an image mapped to a specific memory location holding their binary colour value.
- 43What is a pixels?It is the smallest possible addressable area defined by a solid colour, represented as binary in an image.
- 44what is an image resolution?It is the number of pixels and image contained per inch or per centimetre.
- 45What is a screen resolution?It is the number of pixels per row by the number of pixels per colour.
- 46What is a digital image?It is composed of pixels arranged in a rectangular array with a certain height and width.
- 47What are vector graphics?Images are represented as mathematical formula that define all the shapes in the image such as lines, polygons and text.
- 48What is sound?Sound is an oscillation of pressure transmitted through a solid, liquid or gas.
- 49ADC?It converts analogue sound into digital signals that can be stored on a computer.
- 50DAC?converts digital signals that can be stored on a computer into analogue sound that can be played through devices such as speakers.
- 51Bit rate?bit rate is the number of bits required to store one second of sound.
- 52sample rate?number of samples per second.
- 53sample resolution?Number of hits per sample.
- 54Bit rate?Number of bits required to store 1 second of sound.
- 55what is a video?A video is an electronic medium for the recording, copying and broadcasting of moving visual images.
- 56Frame rate?It is the number of still pictures per unit time of video, ranges from 6 or 8 frames per second.
- 57RFID reader?It is used to read data without physical contact which has a radio frequency identification chip.
- 58CRT?A CRT is a visual display unit which was mostly used in all fat television.
- 59what is cache memory?cache memory is a type of memory which is very fast and is used to improve the speed of a computer doubling it in some cases.
- 60de morgan's law?de morgan's law are used to simplify boolean's equations so that equations involving one sorted gate generally used in NAND or NOR gates can be built.
- 61Library software?Library software are a collections of resources used to develop programs.
- 62assembler?it translate assembly language into machine code.
- 63adv of assembler?- very fast
- take less memory
- easy to understand - 64compiler?translates code written in hll to a lll , machine or object code.
- 65adv of compilor?-the source code is not included.
-its faster
-it produce executable file. - 66disv of compilor?-obj code needs to be produced.
-the source code must be 100% correct. - 67interpreter?an interpreter executes other programs directly running through program code executing it line by line.
- 68adv of interpreter?-easy to debug
-easy to cr8 - 69disv of interpreter?-usually slower programs
-source code required
-can be insecure - 70Processor?a processor is the most complex part of the computer system.
- 71what does the processor contains?- control unit
-arithmetic and control unit
- registers - 72registers?they are special memory cell which operate at very high speed.
- 733 buses?- control bus
-address bus
- data bus - 74address bus?it is a signal directional bus that carries address signals from the cpu to main memory and input, output devices.
- 75data bus?it is a bi-directional bus consisting of 32 wires used to transport data and instructions between the 3 components of the cpu.
- 76control bus?it is a bi-directional bus consisting of more than 16 wires used to control signals between the 3 components of the cpu.
- 77Input/output controllers?It is an electronic circuit connected to the system bus and in an i/o device.
- 78I/O ports?I/o ports is a method of performing input or output between the cpu and the peripheral devices and the computer.
- 79control units?The control unit sits inside the cpu and coordinates the input or output devices.
- 80Clock?The processor clock is a timing device connected to the processor which synchronises when the fetch-decode execute cycles run.
- 81clock speed?it is the number of cycles that are performed by the cpu per second.
- 82examples of registors?- general purpose register.
- address register.
-conditional address register. - 834 registers which are important?- program counter (PC).
- memory address register.
-memory buffer register.
-current instruction register. - 84program counter?An incrementing counter which keeps track of the memory address of which instruction is to be executed next.
- 85Memory address register?Holds the address in memory of the next instruction to be executed.
- 86Memory buffer registor?A two way register which holds data fetched from memory or data waiting to be stored in memory.
- 87current instruction register?A temporary holding ground for the instruction that have just been fetched from memory.
- 88how to increase performance of processor?-Increase clock speed
-Increase word length
- increase bus width - 89fetch-decode execute cycle?It is the process by which a computer
- fetches a program instruction from its memory
-determines what instruction wants to do
- carries out those actions. - 90MAR(memory address register)The address in main memory which is currently being read or written.
- 91MBR ( memory buffer register)A two way register which holds data fetched from memory and ready for the CPU to process or data waiting to be stored in memory.
- 92CIR (current instruction register)It is a temporary holding place being fetched from memory.
- 93register notation?To describe the fetch-decode execute cycle.
- 94Status register?It contains bits which are set or cleared based on the result of an instruction.
- 95Types of interrupt:-Interrupt generated by the running process
- I/O interrupt
-Timer interrupt
-Program check interrupt
-Machine check interrupt - 963 terms that are used for building data requirements?- entity
-attributes
-relationship - 97entity?it is an object, a person, an event or something of interest to an organisation about which data is to be recorded.
- 98attributes?it is a property or characteristic of an entity.
- 99relationship?a relationship is a link or association with two entities.
- 100artificial intelligence?It is a science concerned with the general study of intelligence in all its forms both in living organisms and in present machines as well as future machines.
- 101Digital divide?It is the disparity between groups when accessing information and communication technologies.
- 102several problems of data?-data redundancy
-data inconsistency
-lack of flexibility
-data was not shareable - 103DBMS(database management system)it is a software used to control access to data in a database.
- 104feature of dbms?-program data independence whereby the storage structure of the data is hidden from each application or user.
- restricted user access to the data that is each user is given a limited view of the data according to the needs - 105data dictionary?a data dictionary describes the structure and attributes of data items to be used within a software application usually a database.
- 106normalisation?it is the process used to keep the database as efficient as it can be without any unnecessary duplication and no redundant data.
- 107rules of normalisation:-organise data efficiently.
-eliminate redundant data.
-ensure that only related data are stored in a table. - 108intranet?it is a private network within an organisation which many offer file sharing, printer sharing, private website, etc..
- 109Packet switching?It is the method by which the internet works. It features delivery of packets of data between devices over a shared network.
- 110a domain name service? ( DNS)It translates domain names meaningful to human into IP addresses for the purpose of locating and addressing the devices worldwide.
- 111protocol?it is a set of rules governing the way that devices communicate with each other.
- 112port number?it is an application or process specific communication endpoint to an IP address.
- 113FTP(file transfer protocol)it is a standard network used to copy a file from one host to another over TCP/IP.
Informationen
- Beschreibung
- This is some notes about computer and my exams are next week.
- Erstellt von
- jason_2431
- Aufrufe
- 161
- Tags
- Bewertung