Download system software

College of Information Technology / Software Department
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Computer Skills II / First Class / Second Semester
LEC. 12
Programs, Applications, and software
 Software
Software is a general term for the various kinds of programs used to operate computers
and related devices. Software is any set of machine-readable instructions that directs
a computer's processor to perform specific operations. Computer software contrasts
with computer hardware, which is the physical component of computers. Computer
hardware and software require each other and neither can be realistically used without the
other.
Software provides instructions that tell the hardware what to do, both software and
hardware work together to perform the tasks requsted by the user. There are two major
types of software, namely system software and application software, system software
manages and integrates a computer's capabilities but does not directly perform tasks that
benefit the user, system software includes operating systems and any program that
supports application software, application software includes programs that users are
directly interested in.
Software
Application Software
System Software
OSs sucha s Wndows, MacOS, Linux, etc. tell
the computer how to interpret commands,
mnage files, process input and output, etc.
Once the OS is running, software
can be installed and various
programs can be run to enable the
user to perform specific types of
tasks with the computer.
OS must be present before any other
software, such as a word processor, can run.
Software is essentially a program which is a set of coded instructions that a computer can
understand to solve a problem or produce a desired result. Two basic types of computer
programs are (1) an operating system, which provides the most fundamental instructions a
computer uses in its operations, and (2) an application software , which runs on
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the operating system and does a specific job such as word processing. Application
software cannot run on itself but is dependent on system software to execute.
An operating system is like the software administrator of the computer, managing
interactions between hardware and applications. It’s one type of system software, which
is the software that the system uses the user doesn’t interact with it directly.
When you buy software, you normally buy an executable version of a program. This
means that the program is already in machine language, it has already been compiled and
assembled and is ready to execute.
Some general kinds of application software include:
- Productivity software, which includes word processors, spreadsheets, and tools for use
by most computer users
- Presentation software
- Graphics software for graphic designers
- CAD/CAM software
- Specialized scientific applications

program
A program usually requires an installer and will install various files needed on the
computer for it to work. A program will include and require an uninstaller in order to get
deleting the various files installed all over your hard disk.
In a computing context, software and program are mostly synonymous. Software can be
made up of more than one program, however, and if you’re talking about a product, it’s
usually called software.
Programs consist of an organized list of instructions that written to perform a specified
task on a computer, when executed, causes the computer to behave in a predetermined
manner. A program contains a list of items (called variables) and a list of directions
‫( توجيهات‬called statements) that tell the computer what to do with the variables. The
variables can represent numeric data, text, or graphical images, etc.
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There are many programming languages C, C++, Pascal, VBASIC,FORTRAN, COBOL,
LISP , Java, C#, etc., these are all high-level languages. One can also write programs
in low-level languages called assembly languages, although this is more difficult. Lowlevel languages are closer to the language used by a computer, while high-level languages
are closer to human languages.
Typically, the program is put into a storage area (memory) accessible to the computer,
the computer gets one instruction and performs it and then gets the next instruction, the
memory can also contain the data that the instruction operates on, the program's
instructions are executed in a central processor. The program has an executable form that
the computer can use directly to execute the instructions.
Source code may be converted into an executable file (sometimes called an executable
program or a binary) by a compiler and later executed by a central processing unit.
Alternatively, computer programs may be executed with the aid of an interpreter,
eventually ‫أخيرا‬, every program must be translated into a machine language that the
computer can understand. This translation is performed by compilers, interpreters,
and assemblers.
The instructions, which we will call statements, look different in different programming
languages, but there are a few basic operations most languages perform:
input: Get data from the keyboard, or a file, or some other device.
output: Display data on the screen or send data to a file or other device.
math: Perform basic mathematical operations like addition and multiplication.
testing: Check for certain conditions and run the appropriate sequence of statements.
repetition: Perform some action repeatedly, usually with some variation.
Every program you've ever used, no matter how complicated, is made up of statements
that perform these operations. Thus, one way to describe programming is the process of
breaking a large, complex task up into smaller and smaller subtasks until the subtasks
are simple enough to be performed with one of these basic operations.
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Programming errors are called bugs and the process of tracking them down and correcting
them is called debugging.
 Application
An app will usually be (or at least feel like) one file downloaded, it will have one icon.
An application (the short form of application program) is software that performs a
specific function directly for the user, allows you to perform specific tasks, or in some
cases, for another application program. An application is a program, or group of
programs, that is designed for the end user.
Applications for desktop or laptop computers are sometimes called desktop applications,
and those for mobile devices are called mobile apps. When you open an application, it
runs inside the operating system until you close it. Most of the time, you will have more
than one application open at the same time, and this is known as multitasking.
An application is a program that interacts with a human directly. For example, the driver
for your video card is a program (or probably a set of programs) but it is not an
application, your operating system is a program, but it is not an application, your browser
is an application.
Examples of applications include word processors, database programs, Web browsers,
development tools, drawing, paint, image editing programs, and communication
programs. Applications use the services of the computer's operating system and other
supporting applications.
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