Software
portion of the computer system which provides instructions to the hardware on how to perform tasks.
Two Types of Software
◦System Software
◦Application Software
System Software
It provides the basic non-task-specific functions of the computer.
It is responsible for controlling, integrating, and managing the individual hardware components of the computer system.
Kinds of System Software
Operating System
Utility program
Operating System
manages a computer’s resources and acts as intermediary between a user and the computer resources.
Basic Functions of OS
Memory Management
Resource Allocation and Sharing
Backing Store management
Interrupt handling
Allowing users communicate with the computer.
Three (3) types of UI
Command-line interface
Manu-driven interface
Graphical User interface (GUI)
Command-line Interface
displays a prompt, user types on the keyboard, computer executes and provide the textual output
Menu-Driven interface
user has a list of items to choose from and can make selection by highlighting one
Graphical User interface (GUI)
uses windows, icons, pointers, menus
Single user / single tasking operating system
allows one user to run one program at a time
Single user / multitasking operating system
allows a single user to work on two or more programs at the same time
Multiuser operating system
allows two or more users to run programs simultaneously
Multiprocessing operating system
supports two or more processors running programs at the same time
Manage memory
This function optimizes the use of the RAM
Schedules jobs
The OS determines the order in which jobs are processed
Control network
organizes and coordinates how multiple users access and share resources on a network
Administers security
The network administrator uses the network OS to establish permissions to resources.
Stand Alone OS
can operate with or without a network
Network OS
designed a network; resides on a server
UNIX
a networked computer system designed to allow users to share software and to have controlled access to other user’s files. It was developed by Ken Thompson, Dennis Ritchie, and Douglas Mcllroy.
Macintosh OS (MacOS)
an operating system developed by Apple computer.
MS-DOS (MicroSoft Disk Operating System)
an operating system commercialized by Microsoft Corporation. It was initially called QDOS (Quick and Dirty Operating System) developed by Tim Paterson.
Linux OS
an open source operating system developed by Linus Torvalds.
Utility Program
a type of system software that allows a user to perform maintenance-type tasks usually related to managing a computer, its devices, or its programs.
Compiler
converts the entire source program into machine language.
Interpreter
translates and executes one statement at a time
Application Software
It is used to accomplish specific user-oriented tasks.
Two Categories of Application Software
Packaged
Custom
Packaged
mass-produced, copyrighted retail software that meets needs of a wide variety of users
Custom
performs functions specific to a business or industry
Open source software
software providedfor use, modification, and redistribution
Shareware
copyrighted software that is distributed at no cost for a trial period
Freeware
copyrighted software provided at no cost by an individual or a companythat retains all rights to the software
Public-domain software
software that has been placed in the public domain.
no ownership such as copyright, trademark, or patent.
Bespoke
“tailor-made” to meet the requirements of a specific organization.
Off-the-shelf
can be purchased by anyone.
General Purpose
it does a variety of jobs.
Integrated Packages/Software Suites
packages of common productivity tools that are bundled together.
Generic
can be used to perform a number of tasks, not necessarily for which the application was originally designed.
Specific
software that only has one/few application.
Application Software Categories
Business
Graphics and Multimedia
Home/Personal/Educational
Communications
Application Software (AS)
Examples of ______:
Word Processing
Spreadsheet
Databases
Presentation graphics
Desktop publishing
Web browsers
Low Level Languages
1 st GL Machine Language
2 nd GL Assembly Language
1 st GL Machine Language
Instructions are in the form of machine code, 1’s and 0’s
2 nd GL Assembly Language
uses short, English-like, abbreviations to represent common elements of machine code
Procedural Languages (3rd GL)
Uses English-like words to write instructions
Cobol
C Language
Object Oriented Programming (OOP) Languages
implements an object oriented design.
Java
C++
C#