Statistics is a branch of mathematics involved with collection, classification, analysis, and interpretation of numerical facts. Statistics is the study of data (Business Dictionary). There are significant number true samples where statistics are used. For example, you and a friend are at a basketball game, and out of the blue he offers you a bet that neither team will hit a home run in that game. Should you take the bet? (Statistics/Introduction/What is Statistics)

There are mainly two types of statistics, descriptive statistics and inferential statistics. Descriptive statistics gives data that portrays the information in some way. It provides a brief rundown judgment of information. Data can be summarized numerically or graphically as you want. For example, suppose a clothing shop sells pants, t-shirt and shocks. If 100 cloths are sold, and 40 out of the 100 were t-shirt, then one description of the data on the cloths sold would be that 40% were t-shirt. (Descriptive & Inferential Statistics: Definition, Differences & Examples)

In inferential statistics we use arbitrary example of data which are taken from a population to describe and aggravate inferences regarding the number. For example, if you want to know the average height of all the women in a town with a population of so many million residents. It will not be practical to get the height of each woman. In this case inferential statistics comes into play. Inferential statistics are valuable when it is not convenient or possible to examine each member of an entire population.A statistical data may consist of a list of numbers related to a research. Among those numbers, few may be repeated twice and even more than twice. The repetition of number is a data set is termed as frequency of that particular number or the variable in which that number is assigned. The frequencies of variables in a data are to be listed in a table. This table is known as frequency distribution table and the list is referred as frequency distribution (Frequency Distribution)

Here are the types of frequency distributions:

Grouped frequency distribution: it is an arrangement class intervals and corresponding frequencies in a table.

Ungrouped frequency distribution: it is an interval width of 1 and arrangement of the observed values in ascending order. Data are not arranged in groups.

Cumulative frequency distribution: in this distribution, the frequencies are shown in the cumulative manner. It can be defined as the sum of all previous frequencies up to the current point.

Relative frequency distribution: If the frequency of the frequency distribution table is changed into relative frequency then frequency distribution table is called as relative frequency distribution table. For a data set consisting of n values.

Relative cumulative frequency distribution: It is the cumulative frequency divided by the total frequency (Frequency Distribution)