The 7 Basic tools for Quality Management
Cause-and-effect diagram (also called Ishikawa or fishbone chart): Identifies many possible causes for an effect or problem and sorts ideas into useful categories.
Check sheet: A structured, prepared form for collecting and analyzing data; a generic tool that can be adapted for a wide variety of purposes.
Control charts: Graphs used to study how a process changes over time.
Histogram: The most commonly used graph for showing frequency distributions, or how often each different value in a set of data occurs.
Pareto chart: Shows on a bar graph which factors are more significant.
Scatter diagram: Graphs pairs of numerical data, one variable on each axis, to look for a relationship.
Stratification: A technique that separates data gathered from a variety of sources so that patterns can be seen (some lists replace "stratification" with "flowchart" or "run chart"; the latter is within the description of a scatter diagram).