2.5 Functions of an OS & 2.6 Software Applications Flashcards
OS
a set of software that controls the computer’s hardware resources and provides services for computer programs
functions of an OS (IB)
- acts as an intermediary between software applications and the computer hardware
- peripheral communication
- memory management
- resource monitoring and multitasking
- disk access and data management
- security
functions of an OS (IGCSE)
- input & output control
- human computer interface (HCI)
- multitasking
- multiprogramming
- batch processing
- error handling
- loading and running of applications/software
- management of user accounts
- file utilities (i.e. copy &paste)
- processor managementt
- memory management
- real-time processing
- interrupt handling routines
- security
types of user interface
- GUIs that have menus and icons
- CLIs where the user types in codes
- NLIs where the user speaks to the interface
- MBIs that give the user a selection of options
what does GUI stand for
graphical user interface
what does CLI stand for
command line interface
what does NLI stand for
natural language interface
what does MBI stand for
menu based interface
what are peripheral devices
all hardware components of the computer system that reside outside the CPU
OS and peripheral devices
- communicating directly with the hardware
- providing an interface between hardware and applications
OS and memory management
- manages how the memory is used by applications
- ensures one application does not interfere with the memory of another
- allocates/deallocates specific sections of memory to each program
OS and resource monitoring and multitasking
- efficient allocation of resources
- sharing the CPU between applications at the same time
types of resources on an OS
- the amount of memory used
- how much processor time it needs in order to function
OS and disk management
- making sure applications don’t override files
- coordinating transfer of data from disks files into primary memory (vice versa)
security and the OS
- identity to the user for authentication
- username & password (also magnetic cards and biometrics)
- use of log files that trace the activity of users on the computer system
main software applications
- word processors
- spreadsheets
- database management systems
- web browsers
- computer-aided design (CAD)
- graphic processing software
word processors
- tools for composition, editing, formatting, and printing
advantages of a spreadsheet
- speed
- accuracy
- auto-calculations
what does DBMS stand for?
database management systems
- envelope, header, and the body
- SMTP used
- web-based or software
the disadvantage of web-based email software
need to be connected to the internet while using it
message header contains
information about the sender and recipients addresses, and the subject field and date/time stamp
examples of uses of CAD
- automotive
- shipbuilding
- architectural design
CAD aspects
materials, dimensions, tolerances
common features of applications
- GUIs to allow the user to interact with the interface in a number of ways (not just commands)
example components of GUIs
- graphical icons
- visual indicators
- toolbars
-menus - dialogue boxes
Pros of CLIs
- easier to implement by the programmer
- requires less memory to run
- can be run on computer systems without graphical monitor
- quicker to type command than to use mouse
Cons of CLIs
- users need to remember specific commands
Pros of GUIs
- users do not need to remember specific commands
- users use icons to remember commands
- commands are grouped in menus
Cons of GUIs
- more complex to implement by a programmer
- requires more memory
- requires a graphical monitor and a pointing device
acronym for GUIs
WIMP
Windows
Icons
Menus
Pointers
