Reports are a way for researchers to publish information about ongoing research or a recently completed research project. Reports are often published by a university or research institution and, compared to journal articles and books, they are published much faster. Just like dissertations, although not to the same extent, reports may contain both research overviews and references to earlier research.
These reports are usually published in a series and called working papers, discussion papers, technical reports, or research reports.
Note: the above content is directly quoted from the University Library Guides offered by the University Library at Jönköping University