3. Software Flashcards
Name 5 different high level languages
Python, Java, Ruby, C#, C++
What are the three main types of software?
System software
Application software
Utility software
What is the definition of software?
The programs that are run on computers and also can be the data that the programs use.
Programs are stored sets of instructions that are given to processor to carry out.
Describe the software in a dedicated system
Stored in chip
Specific to job
Eg. Washing machine only specific to washing
What is the system software and what is its function?
It is the software that controls the hardware. Takes care of movement of data between locations. It is intermediary between application and hardware.
- hides complexity of hardware from user and application programmer
- allows user to operate computer without programming
What is main part of system software?
What is the definition?
Operating system.
Set of programs that controls hardware and allows user and applications to work with the computer.
How does OS control software and hardware?
Through the API (application program interface), which manages sharing of internal memory by applications running on the computer.
It handles input and output to and from attached hardware devices through device drivers (software)
What is the order of sequences after the computer is turned on?
ROM loads BIOS (basic input and output system) and hardware tests to ensure that everything is working.
Then loads boot sequence.
Then OS transfers from secondary storage to RAM to CPU and applications can be run
What is the heart of the OS and what does it do?
Kernel.
It controls the hardware with the device drivers
What are the main functions of an OS?
1) memory management
2) provides interface (to mask complexity)
3) maintains security and access rights of users
4) peripherals management
Explain the relationship between an application and OS
Application performs useful real-world job.
OS controls hardware
What is the user interface and what does it do?
It is the means by which the user reacts with a computer, particularly by using inputs and software.
It lets the user input commands, asks questions and displays a response.
What are the advantages/ disadvantages of CLI and GUI?
CLI (command line interface) is good for flexibility and control, able to group commands (she’ll scripts) and quicker to operate when learnt, but needs to be memorised
GUI (graphical user interface) uses WIMP (windows, icons, menus, pointers) so easy to navigate and need not be learned, good for touch screens/no keyboard availability, however less flexible
What are maintenance actions that can be achieved with a typical GUI?
Selecting software and files Controlling sound volume Connecting to WI-FI Deleting/moving files Checking battery Updating/installing software
What are pros and cons of speech as input?
Good for inputs on telephone, giving commands to computers and dictating text
Hard to get work due to accents and dialects, speed and clarity of talking
What does memory management do?
Divides memory into pages Loads processes (program being executed) into vacant pages
What happens in the technique of virtual memory?
Occurs when not enough storage on RAM
OS swaps jobs in and out of memory (parts of program not needed are stored in secondary memory) by dividing programs into modules
Name three types of files
Data files- document or database
Program files- OS components or applications
Configuration data- eg. Part of OS registry
What happens when you save a file?
OS looks where there is free space in storage
Writes data to storage and records location
When you next open file OS looks up location, finds and retrieves it
What is defragmentation?
Process of locating noncontiguous fragments of data and rearranging them into fewer fragments or whole file
Why is defragmentation necessary?
Main memory is divided into segments
Files larger than segments are split into blocks across many segments
Takes longer to read/write
Defragmentation used to move blocks next to each other in storage to increase speed
What are device drivers?
Software that allows OS to communicate with and operate with devices
What is a directory and why are they useful?
A logical grouping of files (could be called folders on Windows)
Make it easier for human to locate related files
Allow repeated use of same file name in different locations
What are file attributes?
Extra information about the file eg.:
- who created it
- who can view/edit it
- if it is read-only
- size of file
What are viruses?
Malicious programs that replicate themselves, designed to damage files, take control of computer and retrieve confidential data
What is authentication of users?
When OS can be set up to check users are themselves
Uses user id and password to check user’s privileges
What are privileges?
The rights assigned to users and groups that include if user can view, write or execute particular files/programs
Why are some files encrypted?
So an unauthorised person can’t understand them eg. Passwords
What are editors?
What are they used for in particular?
Word processors with limited ability that allow text files to be:
Created, saved, read, changed
Used for writing source code and editing configuration files
What are linkers and interpreters?
Linkers combine modules of object code into an executable program
Interpreters convert typed commands into machine instructions
What is difference between applications and utilities?
Applications are software that the user uses eg. Word processor, calculator
Utilities usually run in the background and help maintain the computer
Name the security utility programs and their functions
Antivirus- detects and removes self-replicating programs
Spyware- detects and removes programs that record your history and passwords
Firewall- monitors traffic entering and leaving system in order to block unauthorised material
What are some disk organisation utilities
Formatting, file transfer, defragmentation
What are advantages and disadvantages of custom written software?
Advantages:
-not available to your rivals
-developed specifically to your requirements
-the developer will solve any issues
Disadvantages:
-expensive
-maybe long time to develop or not tested much
What are advantages and disadvantages of off the shelf software?
Advantages: -readily available -extensively tested -many users = lots of help and testing -cheap Disadvantages: -not specific to customer -may need expensive customisation -no competitive edge
What are advantages and disadvantages of open source software?
Advantages:
-usually free
-source code available so can be modified
-reliable and efficient as many people work on it and have help forums
Disadvantages:
-updates not always regular
-anyone can edit so malicious users could too
What are advantages and disadvantages of proprietary software?
Advantages: -helpline to contact -extensively tested -regular updates Disadvantages: -expensive -inflexible to users needs -source code protected
