What are the tools are mainly used for information gathering

1.  Record review: A review of recorded documents of organisation is performed.Manuals procedures, forms and books are reviewed to see functions and format of present system. Search time in this technique is more. 

2.  On site observation: In case of real life systems, actual site visit is performed to get a close look of system. It helps analyst to detect the problems of existing system.

3.  Interview: A personal interaction with staff is performed to identify their requirements. It needs experience of arranging the interview, avoiding arguments, setting stage and evaluating the outcome. 

4. Questionnaire: It is an effective tool that requires less effort and produces a written document about requirements. It examines a large number of respondents concurrently and gets customized answers. It gives person sufficient time to answer queries and give correct answers.