** **Statistics is a branch of scientific method comprising of collection, presentation, analysis and interpretation of data which are obtained by measuring some characteristics. However, the word statistics is used in both singular and plural forms. For example, statistics is now taught in various disciplines- this is singular sense, whereas the statistics of industrial production of India for the last five years- this is plural sense.

Numerical figures which are the effect of a large number of causes only comprise statistical data. A single train accident is not a statistical data, but the total number of train accidents during a year constitutes the statistical data. A table of values of a mathematical function viz., cos x, log x etc. will never be called statistical data. Statistics deals with quantitative data only. However, methods have been devised to transfer qualitative data to quantitative.

Statistics is a wide subject and find a very suitable place in various aspects of life. Statistical tools are used in agriculture, biology, behavioral science, geology, physics, psychology, medicines, engineering etc. In business and commerce the statistical tools viz., demand analysis, forecasting, inventory control, net Nork scheduling etc. are needed for proper organization. For manufacturing industry statistical quality control and sampling theory are two important statistical tools.

Success in Operations Research in military operation and in other phases is because of statistics.

The following steps are carried out for any statistical experiment.

(a) **Collection of data.** The problem which has been formulated requires data for investigation which are collected by any physical methods and techniques.

(b) **Tabulation.** The data which we have collected can be considered as raw data and we do not get any insight of the problem unless we go for tabulation, i.e. .. represent the data in simple tabular form by diagrams, bar charts, pie charts etc. Construct the frequency distribution.

(c)** Statistical inference**. Apply the statistical methods on the tabulated data and draw conclusions about the unknown properties of the population from which the data have been drawn.