What is the difference between use case report & a data flow diagram

oh my god... i don understand waz wrong with these ignou kids..MCA 1st sem....i myself am an ignou student and was searching through the information and bumped into this web site..so many ignou students asking for the answer...don u people understand that how can u get such big answers here..this is a forum where u can ask for questions and may get one line answer coz people are here to help each other but they are not here to write assignments for u....This guy Christopher is given a good answer to all of u...i still don believe u ignou students asking such questions here...These answers are not easily available and u need to research on Use case diagram /dfd/request for proposal and request for information and combine answers from muliple places..don expect that u get the answers very easily...

A use case is an OO tool used to show the interaction between behavioural elements of a system (use cases) and elements of the 'outside world' (actors). Use cases are generally used in the requirements analysis stage. A DFD is a tool dating back to pre-OO days and is used to show the flow of information within a system. It can be used as part of the requirements analysis stage (to illustrate existing flows) or as part of the logical or physical design stages to illustrate planned flows.

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