information. This work explored the various research methodologies as applied to information system with a focus on application development. Various research methodologies have been extensively discussed with a view to establishing the effects of wrong usage of research method by digging out the importance of the right usage of research methodology. The study reviewed 63 research works highlighting the author, year of research, aim of each research, the method used as well as the result of the finding. The result confirmed that adopting the right method for every research gives accurate results while wrong usage of research methodology leads to false outcome. This has great implications for information system development and sustenance. Keywords: Information Systems, Methodologies, Reviews, Research, Usage, Methods, Outcomes.