Descriptive statistics are numbers that summarize data, such as the mean, standard deviation, percentages, rates, counts, and range. Descriptive statistics simply describe the data but do not try to generalize beyond the data.
For example, we can describe starting salaries of college majors by calculating the mean salary and the range for each type of major. We can also describe the percentage of college graduates by major who obtain jobs within six months of graduation.
To be able to generalize beyond the sample, you need to use inferential statistics.