The document provides an overview of software, defining it as a set of instructions that enable computers to perform specific tasks. It outlines different categories of programming languages, including low-level and high-level languages, and discusses the roles of operating systems and application software. Additionally, it distinguishes between source programs and object programs, emphasizing the importance of translators in converting code for computer comprehension.

1. Class. No: 253
Department of English,
Abdul Wali Khan University Mardan

2.  The term software is used for a sequence of instructions
given to the computer to perform a specific task.
 The set of instructions that takes data from input
devices, manipulate and process the data, and send it to
an output device is called “software”.

3.  Programming is the process by which a set of
instructions is written for a computer to perform some
specific activity.
 Programs written in computer are referred to as
“Software”.

4.  Flow Chart:
Computer
Software
LANGUAGES
System Software
Application
Software
High Level Low Level
Operating
System Translators
Application
Packages
Customized
Packages

5.  Low level Languages: Low level computer languages are machine
codes or close to it.
 For example: 0 and 1
 Low level languages are further divided in to;
o 1) Machine Language: It expresses instructions in the binary
codes of computer i:e 0 and 1.
o 2) Assembly Language: It utilizes symbols to represent operation
codes and storage locations, also called symbolic language. It is
alphanumeric language known as “mnemonic codes”.
o Example: ADD for Addition, SUB for subtraction, start label etc.

6.  Very close to English Language.
 They are basically symbolic languages which use English
words and mathematical symbols rather than mnemonic
codes.
 Each instruction in this language is translated into many
machine language instructions.
 Example: PL/1 (Programming language, version 1), C
Language, GPSS etc

7.  Programs which hold instructions related with the working of
hardware and software of the computer system.
 The set of programs which increase the capabilities of the
system and to make the use of computer more effective.
 They are also called “Firmware”.
 Further divided into two categories.

8.  A set of programs which coordinate and control
computer operations.
 They provide communication between the user and
the computer hardware.
 Main functions of OS are :
 Job control
 Memory management
 Supervisor
 Multiprogramming
 Produce error messages

9.  Before defining translators, the following terms must be
defined:
a. Source Program: A program written in non-
machine language. For example, a program written in
assembly or high level language like FORTAN, COBOL
etc is source program.
b. Object Program: The source program is translated
into machine language. The translated program is called
Object Program.

10.  The translation process is pictorially represented as
follow:
 According to this diagram, translators are programs which convert
instructions in assembly or high level languages because computer
can only understand machine language.
SOURCE
PROGRAM
TRANSLATOR
OBJECT
PROGRAM

11.  They are also known as “packages”.
 They help the users to require their required
outputs.
 These are the software developed by experts in
high/low level languages for non-experts.
o There are two types of Application
software/packages:
I. Application software/packages
II. Customized Packages

12.  The general programs in the market developed by
famous software development companies are
known as Application Programs. E.g.
 Word processors: word star, MS-word etc.
 Games: IGI, Chicken invaders, FIFA
 Spread sheets; Lotus, Excel etc
 Graphics: Haward Graphics, Instant Artist.
 Educational: Medicine, Commerce, Archeology etc.

13.  These are developed according to the needs of an
organization.
 The program can be developed by a single
programmer or by a team of programmers
depending upon the requirements. E.g.
Programming for:-
• Banking
• Accounts
• Industries
• Stock and sales etc.