Final answer:
The two types of control charts used for attributes data are the p-chart, which is used for binomial data to plot proportion of defects, and the c-chart, for count data to display occurrences per unit.
Step-by-step explanation:
When dealing with attributes data in quality control, two types of control charts commonly used are the p-chart and the c-chart. These charts are helpful for monitoring the variation in processes dealing with categorical data.
p-chart (Proportion Chart)
The p-chart is used when the sample size is greater than one and the data is binomial; that is, it can have only two outcomes (e.g., pass/fail, defective/non-defective). It plots the proportion of defective items out of the total number of items checked.
c-chart (Count Chart)
The c-chart is used for count data, suitable when the number of occurrences per unit of measure can be counted; for instance, the number of scratches on a car door.