Chapter No 1

SOFTWARE ENGG NOTES BY- MANJUNATH.M.PATIL!

CHAPTER NO 1

SOFTWARE AND SOFTWARE ENGG

Software:- A set of programs is called software.

Software engg:- Who has to develope and manage the software projects is called software engg

Definition of software engg:- "The software engg is defined by the application of technologies in a systematic manner with well maintain technique that can develope a software product with in time and cost estimation"

Evolving role of Software

Software is a product and also a vehicle for delivery a product as a product it gives all services like computation,modification,verification to all its users. As a vechicle acts as a base of other software product such as operating system for application software(product). The different changes that have occured during the last two years in the software field are:

1) Increase in memory and software capability

2) Variety of input and output options

3) Good method to support the complex processing.

Evolution of Software

During the early years of the software with limited distribution and application it is not so simple in the computing area . example:ms-dos(microsoft disk operating system) .

In the first era of the computer evolution the multiprogramming and gui was developed by the programmers and the new softwares and hardwares are included on the first era in the computer field. Errors and faults were noticed as new statements these were added as part of software. This gave rise to software maintenance.

"The activities like fault detection,modification,application of new hardware and software is termed as software maintenance".

The third era of computer evolution included the feature of distributed computing ,global and local area of networkds with high digital common bandwidth,were also of importance.

In the fourth era that networkds is used powerful destio machines with supported centralized and client-server architecture. In other term global sharing and information was supported.

software application :-

software can be applied for different purposes in different situations the different situations are

1) System software :- A software that provides services to other programs it is characterised by heavy interaction of computer resources.

2) Real time software :-A software tha analysis and using the real world events as occur is called as real time software it controls the monitoring of real world events ,monitoring components,co-ordinating components.

ex:- software is used in rocket launching

3) Business software :- It is a largest application in the software which is used in the (school,railway reservation,government offices etc) specify that the software is used in the restricted area, the specified software is used in specific purpose the same software is not used in other businesses.

4) Personal computer software :- It is a simplest software that are used in the desktop processing like ms-word,powerpoint etc are the computer softwares which is used to the desktop machines for the reason of it is simplest to use in yours computers.

5) Artificial intelligence software :-It is the software that solves all the complex problems in the robotics and in the machine architecture in the any machines like electronic goods.

ex :- robotos

Software Characteristics :-

1) Software is custom builded rather than assembled from an existing components.

2) software is developed and not manufactured.

3) Software doesn't wear-out.

Definition of software engg :- The software engg is defined as a application of technologies in a systematic manner with well maintain technique that can develop a software product with in time and cost estimation.
Factors of software engg :- The factors of software engg is divided into 3 factors are:-
1) Size factor
2) Time factor
3) Quality factor
1) Size factor :- This factor may be distribution of efforts ,efforts are divided as software engg and software maintenance effort. In the development phase if advanced tools and techniques that can develop a software product, then maintenance of software becomes easier
The size of project can be distribution with efforts and team members the project size is classified as follows
1) Small size of 10 to 20 kb of 1 to 6 days by one programmer.
2) Medium size of 50 to 5000kb of 2 to 5 months by 2 to 4 members.
3) Large size of 5 to 20 members working at 5000kb to 500mb at 1 to 6 years.
2) Time factor : - The detail study as shown that the most of the programmers spent in other activities rather than software development.

For example :-

Writing a programme ……………….. 13%
Reading programe and Mannual ……. 16%
Job communication ………………… 32%
Personal talk ………………………… 15%
Services …………………………….. 05%
E-mail ………………………………. 06%
Miscellaneous ………………………… 13%

The failure is found at due to 39% of programmer’s time in the above example shows that in the example and it manages the time factor.

3) Quality factor : - The Quality of factor depends of skills of programmers and management skills, programmer’s time and the cost estimation etc।