The TI-83 Plus is a graphing calculator that is commonly used by students in high school and college. It has a variety of features that can be used to perform mathematical calculations, including the ability to find the standard deviation (SD) of a data set.
The SD is a measure of how spread out a data set is. A smaller SD indicates that the data is more clustered around the mean, while a larger SD indicates that the data is more spread out. The SD can be used to compare the variability of different data sets or to determine whether a particular data point is an outlier.