According to Hart (1999) literature review is the use of ideas in the literature to justify the particular approach to the topic, the selection of methods, and demonstration which contributes to something new to the study. While Leary, (2004) explains literature review as one piece of research that builds on another or creates a firm foundation for advancing knowledge. So it can be deduced that a literature review is an evaluative report of studies found in the literature related to a selected area. The review describes, summarizes, evaluates and clarifies the literature. Literature review should give a theoretical basis for the research and help to determine the nature of the research by selecting a limited number of works that are central to the area rather than trying to collect a large number of works that are not as closely connected to the topic area.
Literature review is essential because it identifies the problem of the study, which can be solved by collection of