Sometimes referred to as the seven statistical tools, or seven traditional tools, these methods to organize or summarize data are an important part of any improvement methodology: histogram (or bar chart), pareto chart, run chart [or line chart], control chart, scatter diagram, flow diagram (flow chart) and cause and effects diagram. Some people list the PDSA cycle rather than the run chart as the seventh tool, or tools that help organizations understand their processes to improve them. The tools are the cause and effect diagram, check sheet, control chart, flowchart, histogram, pareto chart and scatter diagram (see individual entries).