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Video Title: Software Evolution Laws
Description: Software Evolution Laws
Watch more Videos at https://www.tutorialspoint.com/videotutorials/index.htm
Lecture By: Mr. Arnab Chakraborty, Tutorials Point India Private Limited
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In this session, we are discussing
software evolution laws.

Lehman has given laws for software
evolution and he divided the software into

mainly three different categories.

The first one is the static type.

In short, it will be called as S-type.

This is the
software which works strictly according

to the predefined specifications and
solutions.

So, before developing, before starting or
initiating with the development process,

the software respective specifications and
solutions will be pre-known to us.

This solution
and the method to achieve it, both are

immediately understood before starting the
coding operation.

The S-type software is least subjected to
changes.

Hence, this is the simplest of all the
software categories.

For example, calculator program for
mathematical computation we can consider.

So, here all these
recommends are pre-known to us and

the we are also
know the respective method to achieve it.

So, before starting the coding process,
this information will be prior to us and

then we shall start this coding process
and there is a simplest software category.

Next one, we are going for the practical
type.

In short, it will be known as the P-type.

This is a software with a collection of
procedures and this is defined by exactly

what procedures can do.

In this software, the
specifications be described,

but
the solution is not obviously instant.

For example, the gaming software.

If you consider the gaming software, it
will be falling under this practical type.

Here, we are knowing
that we are having certain procedures we

are having and these procedures
we know what they are doing.

And this is defined by exactly what
procedures can do.

In this software, the specifications can be
described, but the solution is not instant.

But in case of S-type, the solution was
pretty known to us.

Next one and the last one is the embedded
type.

In short, it will be called as E-type.

This software works closely as the
requirement of real world environment.

This software has a high degree of
evolution as there are various changes in

laws and taxes, etc.

In the real world
situations, for example, online trading

software should be
a good example of embedded type and E-type.

Here, the multiple time that change
requests will be coming due to the due to

the change in the respective laws in the
taxes and etc.

And this is a software
where different change

requests will go on
getting implemented.

So, obviously, this is a complicated one
and it is real life like oriented.

And this particular software might as we
can be having one example that is an

online trading software.

In the next video, we will be discussing
more on this E-type software evolution.

So, thanks for watching this video.

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