What is the meaning of collection of data?

Concept: Data is at the heart of statistics. Data refers to information or numbers collected for a certain purpose. The plural form of datum is data (the Latin word). 

Statistics is the discipline of mathematics that deals with extracting useful information from a given set of data. 

Its most practical applications are in the real world, where data is used to assess a company's market position. Probability and statistics are used extensively in everyday life, such as in medicine, engineering, weather forecasting, and other fields.

The meaning of a collection of data is to gather some sort of information to prepare a report or to do some analysis on them.