How are informal reports different from routine letters and memos?

Reports are written for many different reasons and use two basic formats. One is the long or formal

report and the short or informal report. But EVERY report, like every letter, essay, or article has 3

main parts: Introduction, Discussion sections, Conclusion. These reports follow the same format as the

memo but are longer and more comprehensive. Because they are longer than one or two pages, reports

also include such formatting elements as headings, bulleted or numbered lists, and graphs and charts

or tables.