On the Web - Publish Linked Open Data means to make it public under the Creative Common License and on can add up to five stars depending on which way one makes the Data available. The first stars requires only make something available on the Web with an Open License.
Machine-Readable Data - This has by definition nothing to do with Linked Open Data, but it is Open Data in that sense. If this Open Data is not only text but also Machine-Readable Structured Data, for example an Excel Spreadsheet instead of an Image Scan of a Table, then it gets already two stars.
Non-Proprietary Format - However Excel is a proprietary Format. If one publishes in a non-proprietary Format, for instance simple CSV Format instead of Excel, then one has three stars.
RDF Standards - Moreover if one uses the W3C Standards which means RDF and SPARQL, then one will get four stars.
Linked RDF - The most important part is when one links the Dataset to other Datasets in the Linked Data Cloud, then one gets the final fifth star.