The document discusses three types of quality charts used in Lean Six Sigma: histograms, Pareto charts, and control charts. Histograms visualize the distribution of process values, Pareto charts identify significant defect occurrences by displaying frequency and cumulative percentages, and control charts indicate process stability by showing project means and control limits. Each chart serves a unique purpose for analyzing process variation and quality control.

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Data Charts
Histograms are frequency charts. In Lean Six Sigma, they show the
distribution of values produced by a process. In other words, a histogram is
a visual display of how much variation exists in a process.
Histogram
A Pareto Chart is a quality chart of discrete data that helps identify the most
significant types of defect occurrences.
It does this by showing both frequency of occurrences (bar graph) and
cumulative total of occurrences (line graph) on a single chart. The type of
occurrences are organized on the X-Axis from highest to lowest frequency.
Respectively, the left Y-Axis shows frequency of occurrences, while the right
Y-Axis shows the total percentage.
Pareto Chart
Control Charts are time charts designed to display signals or warnings of
special cause variation. Graphically, they feature points that represent
project mean or variation, and upper and lower Control Limits. The location
of these points determines if a project is “out of control” and under the
influence of common or special causes.
Control Chart