Law reports in common law countries:

In common law countries, court opinions are legally binding under the rule of stare decisis. That rule requires a court to apply a legal principle that was set forth earlier by a court of the same jurisdiction dealing with a similar set of facts. Thus, the regular publication of such opinions is important so that everyone— lawyers, judges, and laymen can all find out what the law is, as declared by judges.

Official law reports:- Official law reports or reporters are those authorized for publication by statute or other governmental ruling. Governments designate law reports as official to provide an authoritative, consistent, and authentic statement of a jurisdiction's primary law.

Unofficial law reports:- Unofficial law reports, on the other hand, are not officially sanctioned and are published as a commercial enterprise. For the publishers of unofficial reports to maintain a competitive advantage over the official ones, unofficial reports usually provide helpful research aids (e.g., summaries, indexes).

Open publication on the internet:- The development of the Internet created the opportunity for courts to publish their decisions on Web sites. This is a relatively low cost publication method compared to paper and makes court decisions more easily available to the public (particularly important in common law countries where court decisions are major sources of law). Because a court can post a decision on a Web site as soon as it is rendered, the need for a quickly printed case in an unofficial, commercial reporter becomes less crucial.