# Covariance

Statistics is quite an important and perhaps the most vast branch of mathematics. It studies about the collection, organization, analysis and interpretation of numerical data and variables. It provides informative results about data sets that are being used in a number of researches not only in the traditional fields like: maths, science, physics chemistry, psychology, economics ; but also in more modern and technology-oriented areas such as: weather forecast, business statistics, bio-statistics, demography, population survey, data mining, sports statistics, chemo-matrices, reliability engineering and many more.

In statistics, there are different concepts that play an important role in such areas. Covariance is one of them. It illustrates the relationship between two statistical variables. Let us study about covariance in detail.