4. software Flashcards
application software
allows user to perform an activity, specific task eg. word processing, spreadsheet, database, CAD presentation, photo editing web browser
system software
provides the services that the computer requires, including operating system and utility software; 2 types operating system and utility software
opperating system vs utility software
os- software that manages a comp systems cpu, memory, storage, devices, provides user interface allows apps to run eg. windows, macos
utility software- software designed to carry out specific tasks help manage, maintain and control comp resources eg. compression, backup, disk cleaning, antivirus, monitoring, diagnosis, disk defragmentation, encryption, compiler, linker
Operating systems control the computer hardware and act as an interface with application programs. Utility software helps to manage, maintain and control computer resources
roles of operating system (9)
- managing files
– handling interrupts
– providing an interface
– managing peripherals and drivers
– managing memory
– managing multitasking
– providing a platform for running applications
– providing system security
– managing user accounts
what is needed to run applications software and how does it work
hardware, firmware, operating system
applications are run on the os, os is run on the firmware, the bootlander (firmware) is run on the hardware
what are the possible interface types, explain interface
GUI- using windows, icons, menus and pointers
CLI- commands are typed
dialogue- based interface- voice commands
gesture-based interface- touch, virtual reality
providing interface allows user to issue commands and run programs known as HCI
what is the role of os with interrupts
receives and processes requests from peripheral devices,uses a ISR (internet service routine) whcih is what does necessary actions to handle interrupt
ISR is evoked by the os interrupt handler (decides which ISR should be exectued)
interrupt handled and processed, ISR sends EOI t continue with past task
what are interrupts
signals sent from hardware or software to os to request cpu attention when os receives interrupt, suspends current task and executes interrupt in interupt service routine, once interrupt is delt with, os continues with task it was performing before
what are the two types of interrupt
hardware interrupts- generate by hardware devices, eg. pressing a key on the
keyboard and moving the mouse
software interrupts- exceptions, when unexpected events occur eg. division by zero and two processes trying to access the same memory location
describe role of os in managing files
allocates space on secondary storage devices manages creation and deletion of files
describe role of os in handling interrupts
receives and processes requests from peripheral devices
describe role of os in managing peripherals and drivers
os uses system software known as drivers to communicate with peripheral devices
describe role of os in running apps
provides platform for running apps, manages programs that are running on the comp allows user to star or stop programs allows install, updates, uninstall programs
describe role of os in managing memory
controls allocation of ram to individual programs, divides allocation into pages
describe role of os in multitasking
allows to run multiple programs at once, switching between tasks allocating each of them some cpu processing time= scheduling
describe role of os in managing user accounts
it allows several people to have own username and passowrds, os manages these accounts, user cant access files they dont have permission
describe role of os in providing system security
security for computer, computer protected against unauthorised access over internet
explain firmware
firmware is a special software stored in rom, allows comp system to start up and access hardware and os
explain the steps on turning comp on
- comp switchd on firmware executed- instrcuts hardware how to access attached storage device
2.os than started running after firmware retreived from computer storage - application software can be locked and run, or hardware driver
what is meant by high level languages, give advantages and disadvtanges
a type of programming language with high level of abstraction, eg. pthon java, more understandable to humans thus easier to program and faster program development however slower execution and increased memory use
what is meant by low level languages, give advantages and disadvantages
a type of programming lang, lower level of abstraction, not understandbale to human eye eg. c++ and assembly lang, slower to program, more optimised program, increases execution, reduces memory use
what is assembly language
a form of low level language, that uses mnenomics, extrmely close to machine code (lang used by computers) an assembler is needed to translate assembly lang to machine code
machine code
language cpu can process written in binary both high and low level langauges need to be translated into it before program is executed
translators
all programming lang must be translated into machine code, before cpu execution, translator is a software that does this
3 types of translators, assemblers, compilers, interpreters
what do compilers and interpreters do
both essentially do the same thing, translate program lang into machine code however in different ways
how does a compiler work
compilers translate entire program at once, before executing it, and producing an executable file, doesnt execute program until all errors fixed, all erros sent via a report with all erros present in code called compilation, used mainly when programmer has finished programming program, final program
how does an interpreter work
translate 1 line of program at a time, and executes line before translating and executing next line, if errors present on line underneath line currently being translated, the line will still be executed, if error found execution stops used mainly when testing a program quickly, developing a program
advantages and disadvantages of compilers
-executable file produced by compiler, quicker execution, doesnt need any additional software
-can be slow compilation, code must be error less to execute
advantages and disadvantages of interpreters
-code tested even if error made, edit process is faster
-interpretation slows down executing code, interpreter software always required
what is an ide
integrated development environment, software application specifically designed to help programmers create software
what are tools present in ide
- code editors (allow code to be entered)
– run-time environment (programs can be run and tested in ide)
– translators (compiler/ interpreter for convenience)
– error diagnostics (highlights potential errors, and hints suggestions to solve)
– auto-completion
– auto-correction (corrects minor typos)
– prettyprint(formats and indents code to make it easier to read)
