Zusammenfassung der Ressource
Computer Software
- Refers to the programs we run on our computer - the programs
are the stored sets of instructions given to the processor to carry
out. It also refers to the data that is used by the proograms
- Types
- Utility Software
- Has limited functionality and is
used to maintain computer systems
- Application Software
- Handles real-world jobs
that users want to do
- System Software
- Operating System
- Functions
- Memory
Management
- The OS manages the transfer
of data between the CPU,
RAM and main storage
- User Interface
- The OS provides the user with a way of
controlling the functions of the computer
without resorting to machine code
- Command line interface (CLI) e.g. MSDOS.
Commands can be grouped into shell
scripts to carry out maintenance jobs
- Graphical (GUI) e.g.
Windows. Uses icons
to represent actions.
No commands have
to be learned.
- Acts as a boundary between human and machine
- The interface lets users give commands,
ask questions and display a response
- Peripheral Management
- The OS manages the input and output
devices connected to the computer,
like a keyboard, mouse and printer
- Multi-tasking
- The OS allows more than one
program to be run at once so users
can switch between applications easily
- Security
- The OS provides security
features to restrict access to
the system or particular files
- Controls hardware and acts
an an intermediary between
application and hardware
(hides complexities and allows
user to operate computer
without writing programs
- Utility Programs
- Security
- Anti-virus
- Detects and protects the computer against
virus threats and quarantines infected files
- Firewall
- Restrict communication in and out of the
computer from the applications that are running
- Spyware protection
- Detects and removes spyware
(small programs that quietly
monitor what you are doing)
- Disk Operations
- Formatting
- Sets up a hard drive, memory stick or
card into a format that the computer can
use to store/retrieve data. the process of
formatting erases any data that was
previously on the storage medium
- File transfer
- Allows movement of
files from one location
to another, either locally
or via memory stick
- Defragmentation
- Re-organises the data on the hard
drive to improve read/write access time
- System Maintenance
- System info and diagnosis
- Provides information about the system in
order to help with diagnosis of problem
- System cleanup tools
- Removes temporary files and
compresses/archives unused
files to increase free storage
- Automatic updating
- Uses the Internet to check the OS
is up-to-date and applies software
patches/fixes as necessary
- Software
Procurement
- Proprietary
- Written by developers and allowed to be
used by others but with restrictions e.g. can't
adapt software (source code is hidden)
- Extensively tested, updates are scheduled
regularly, reliable, someone to go to if problem
- Source code cannot be inspected so may contain
spyware within the software, expensive, inflexible,
deliberate incompatibilities to lock users in
- Off the shelf
- Developed by a software company
to be sold to the general public
- Cheaper than developing it yourself, tech support
available, extensively tested, ready, forums online
- Inflexible so customisation (not
exact needs), search for traning
- Open Source
- Written by general public for everyone to use.
Source code provided so software can be tweaked
- Allows anyone to use/adopt the software to meet their
needs and a collaborative approach to development
can lead to better quality software, and cheap
- By making source code available to all, provides opportunity
for people to take advantage of software installed on users'
computers compromising security, no or irregular updates,
- Custom Written
- Developed specifically for a particular organisation.
Specially commissioned for a particular customer.
- Meets exact purposes, doesn't require adaptations,
the developer can train, be contacted, and maintain
- Expensive, needs technical expertise to develop,
not extensively tested, time-consuming