In this section, we introduce a number of visualization issues including processing and analyzing steps and technologies.
Handling big data requires a number of extra issues, compared to the general cases of visualization processing and analysis. From a number of sources that generate unstructured data, we need to integrate data by considering different features of data sources. Also it is necessary to have preprocessing step to keep data quality without compromising inherent data character. Among many candidates in tool packages, we need to have the proper insight to choose appropriate visualization method to get expected result. Visualization result cannot be produced if data collection, analysis and refining processes are not properly performed.