Statistics is a branch of mathematics dealing with the collection, organization, analysis, interpretation and presentation of data.Some of the important characteristics of statistics are :
It consists of aggregates of facts, It should be numerically expressed , It must be enumerated or estimated accurately , It should be collected in a systematic manner etc.
The main advantages of statistics are:
they are familiar to library staff and managers
they can be analysed relatively quickly
information is collected in a standardised way
they are usually straightforward to analyse
they overcome the difficulties of encouraging participation by users
hope this helps :)