Volunteered geographic information (VGI) provides an alternative way to produce spatial data by non-professional users. Unlike the traditional process, any user can produce enormously spatial information and make it available for others. Although VGI is considered beneficial for the main reasons such as being free, accessible and up-to-date, quality issue is its obstacle in this context and has been investigated in several scientific studies. Using VGI in various applications,  the quality plays the important role. Therefore; Introducing appropriate assessment tools and methods to improve the quality of data will be an effective way of accelerating the usability of data. One of the possible methods to evaluate VGI quality is determining indicators particularly without usage of reference data. In this paper, we have struggled to overview on the quality of geographic data, then discuss on the quality of VGI from the perspective of the indicators and their evaluating methods specially fitness for use. Moreover, fitness for use will significantly be described in this paper.