What is statistics? According to Oxford Dictionary of English, it is "the practice or science of collecting and analyzing numerical data in large quantities, especially for the purpose of inferring proportions in a whole from those in a representative sample." Statistics are found in tables, diagrams, graphs, charts and so on. 

Here is an example of statistics.

Tourism Indicators by Destination British Columbia.

Why statistics is important to research?  

This video below from Statistics Canada gives you an overview.

What statistics can do for you?

• Strengthen your arguments by providing objective evidence
• Inform decision of daily living and help policy making

Resources for using and writing statistics in your research

• Writing with Statistics pages by Purdue OWL provides overview information, quick tips, basics about writing descriptive and inferential statistics and using visuals with statistics. 
• This Statistics guide by the Writing Centre at the University of North Carolina at Chapel Hill explains what is statistics, and how to read and write statistics. 

Why do you need to evaluate statistics?

There is a such thing as false statistics. Just like any other kind of sources, you need to evaluate the statistical resources you find before using them. You can use the CARS checklist by Robert Harris to evaluate the statistics you find online. 

This guide, How to Evaluate Bad Statistics and Research Method by SUNY Empire State College, gives you some tips on how to evaluate statistics.