Sample of a group is one that includes all the different types of people that are members of that group

Population is the word describe in this sentence:

Sample of a group is one that includes all the different types of people that are members of that group

Population is a group of people that represents the whole number of the particpants or respondents studied in a research or scientific exploration. This is mainly attributed, particed or done in life and social sciences like Psychology, Sociology, Biology and etc.

These sciences use the different sampling methods which some are probability and non probability sampling methods: convenience, cluster, systematic sampling and etc. This is in order to represent the population since sample is the subset of the population, a dynamic analogy.