Original subtitles

suppose you were assigned a task to

develop a custom software for a client

each block below represents a step

required to develop the

software irrespective of your technical

background try and make an educated

guess about the sequence of steps you

will follow to achieve the

task the correct sequence would be

gather as much information is possible

about the details and specifications of

the desired software from the client

this is nothing but the requirements

Gathering

stage plan the programming language like

Java php.net and database like Oracle

MySQL Etc which will best suit the

project also determine high level

functions in

architecture this is the design

stage at actually code the

software this is the build stage next

you test the software to verify that it

is built as per the specifications given

by the client this is the test

stage once your software product is

ready you may do some code changes to

accommodate enhancements requested by

the client this would be the maintenance

stage all these levels constitute the

waterfall method of a software

development life

cycle as you may observe testing in the

model starts only after implementation

is done but if you are working on a

large project where the systems are

complex it's easy to miss key details in

the requirements phase itself in such

cases an entirely wrong product will be

delivered to the client you will have to

start aresh with the

project or if you manage to note the

requirements correctly but make serious

mistakes in design and architecture of

your software you will have to redesign

the entire software to correct the

error assessments of thousands of

projects have shown that defects

introduced during requirements and

design make up close to half of the

total number of

defects also the costs of fixing a

defect increases across the development

life cycle the earlier in the life cycle

a defect is detected the cheaper it is

to fix as they say A Stitch in Time

saves

nine to address this concern the V model

of testing was developed for every phase

in the development life

cycle there is a corresponding testing

phase the left side of the model is the

software development life cycle

sdlc the right side of the model is the

software test life cycle

stlc the entire figure looks like a V

hence the name V model in this figure

you'll find a few stages different from

the waterfall method these differences

along with the details of each testing

phase will be discussed in a later

tutorial apart from the V model there

are iterative development models where

development is carried out in phases

with each phase adding a functionality

to the software each phase comprises of

its own independent set of development

and testing activities good examples of

development life cycles following the

iterative method are rapid application

development and Agile

development before we close this

tutorial here are a few

pointers you must note that there are

numerous development life cycle

models the development model selected

for a project depends on the aims and

goals of that

project testing is not a standalone

activity and it has to adapt with the

development model chosen for the

project in any model testing should be

performed at all

levels right from requirements Gathering

all the way up to maintenance