to tell the reader the topic of your report
to provide a summary of the whole report
to give enough background information to the reader
so they will know the context and purpose of your exp.
to tell the reader what you did, the materials you used, the procedure you followed
to tell the reader what you found
to interpret and explain the significance of what you found
to summarise your findings and interpretations
to tell the reader (in alphabetical order by author) the origin of all the references you have cited the text.
to give more detailed information