• The requirements are collected from the client in a textual format. The prototype of the s/w product is developed. The prototype is just an image / picture of the required s/w product. The customer can look at the prototype and if he is not satisfied, then he can request more changes in the requirements.

• Prototype testing means developers/ testers are checking if all the components mentioned are existing.

• The difference b/w prototype testing and actual testing – in PTT, we are checking if all the components are existing, whereas, in ATT we check if all components are working.

• From “REQUIREMENT COLLECTION” to “CUSTOMER REVIEW”, textual format has been converted to image format. It is simply extended requirement collection stage. Actual design starts from “DESIGN” stage.

• Prototype development was earlier done by developers. But, now it is done by web designers/content developers. They develop prototype of the product using simple ready-made tools. Prototype is simply an image of the actual product to be developed.

Advantages of Prototype model

• In the beginning itself, company set the expectation of the client.
•  There is clear communication b/w development team and client as to the requirements and the final outcome of the project.
• Major advantage is – customer gets the opportunity in the beginning itself to ask for changes in requirements as it is easy to do requirement changes in prototype rather than real  Thus costs are less and expectations are met.

Drawbacks of Prototype model

•  There is delay in starting the real project.
•   To improve the communication, there is an investment needed in     building the prototype.

Applications

 We use this model when,

• Customers are new to the software industry.
• When developers are new to the domain.
• When customer is not clear about his own requirement.

There are 2 types of prototype:

Static Prototype – entire prototype of the requirement is stored in a word document with explanation and snapshots and instructions on how to go about building the s/w, how the finished product will look like and its working etc.

Dynamic Prototype – similar to a browser, but we can’t enter any information. Only the features are available without entering data. It’s like a dummy page, made out of HTML with tags and links to different pages representing features of the project.

Derived model or Customized model – we can take any of the above 4 models and change it as per business needs and requirements.