The waterfall model is a sequential software development process that consists of distinct stages: requirements, design, implementation, verification, and maintenance. In this model, each stage must be fully completed before the next begins and there is no overlap or iteration between stages. While easy to understand, the waterfall model is rigid and not well-suited for complex or long-term projects where requirements may change.

1. WATERFALL MODEL

2. ● Waterfall model was the first process model to be introduced. It is
also referred to as linear-sequential life cycle model. It is very simple
to understand and use.
● In a waterfall model, each phase must be completed fully before the
next phase can begin. This type of SDLC model is basically used for
the project which is small and there are no uncertain requirements.
● At the end of each phase, a review takes place to determine if the
project is on the right path and whether or not to continue or discard
the project.
● The waterfall model is so named because each phase of the project
cascades into the next, following steadily down like a waterfall.
● Earlier this model was very popular but nowadays it is not used. But it
is very important because all the other software development life
cycle models are based on the classical waterfall model.

3. REQUIREMENTS
DESIGN
IMPLEMENTATION
VERIFICATION
MAINTENANCE
WATERFALL
MODEL

4. 1.REQUIREMENTS:
The key aspect of the waterfall methodology is
that all customer requirements are gathered at
the beginning of the project, allowing every
other phase to be planned without further
customer correspondence until the product is
complete. It is assumed that all requirements
can be gathered at this waterfall management
phase.

5. 2.DESIGN:
The design phase of the waterfall process is
best broken up into two subphases: logical
design and physical design. The logical design
subphase is when possible solutions are
brainstormed and theorized. The physical
design subphase is when those theoretical
ideas and schemas are made into concrete
specifications.

6. 3.IMPLEMENTATION:
The implementation phase is when
programmers assimilate the requirements and
specifications from the previous phases and
produce actual code.

7. 4.VERIFICATION:
This phase is when the customer reviews the
product to make sure that it meets the
requirements laid out at the beginning of the
waterfall project. This is done by releasing the
completed product to the customer.

8. 5. MAINTENANCE:
The customer is regularly using the product
during the maintenance phase, discovering
bugs, inadequate features and other errors that
occurred during production. The production
team applies these fixes as necessary until the
customer is satisfied.

9. ADVANTAGES
❏ Simple and easy to
understand and use.
❏ Phases are processed and
completed one at a time.
❏ Clearly defined stages.
❏ Well understood
milestones.
❏ Easy to arrange tasks.
❏ Process and results are well
documented.
❏ Easy to manage due to the
rigidity of the model.
❏ No working software is produced
until late during the life cycle.
❏ High amount of risk and
uncertainty.
❏ Poor model for long and ongoing
projects.
❏ It is difficult to measure progress
within stages.
❏ Cannot accommodate changing
requirements.
❏ Not a good model for complex and
object-oriented projects.
❏ Adjusting scope during the life
cycle can end a project.
DISADVANTAGES

10. THANK YOU