<p>RDF stores can be considered as a subclass of graph databases:</p>

<ol>
<li><p>The central RDF 1.1 notion is <a href="https://www.w3.org/TR/rdf11-concepts/#section-rdf-graph" rel="nofollow noreferrer">RDF graph</a>.</p></li>
<li><p>Many triplestores have word 'graph' in their names: <a href="/questions/tagged/graphdb" class="post-tag" title="show questions tagged &#39;graphdb&#39;" rel="tag">graphdb</a>, <a href="/questions/tagged/blazegraph" class="post-tag" title="show questions tagged &#39;blazegraph&#39;" rel="tag">blazegraph</a>, <a href="/questions/tagged/allegrograph" class="post-tag" title="show questions tagged &#39;allegrograph&#39;" rel="tag">allegrograph</a><br>
(some of them are not only RDF stores though).</p></li>
</ol>

<p>Obviously, there are differences between the RDF model and other graph database models.  These differences are described e.g. in <a href="https://arxiv.org/pdf/1801.00036.pdf" rel="nofollow noreferrer">An introduction to Graph Data Management</a> by Renzo Angles and Claudio Gutierrez.</p>

<hr>

<p>See also <a href="http://www.snee.com/bobdc.blog/2018/04/reification-is-a-red-herring.html" rel="nofollow noreferrer">Reification is red herring</a> by Bob DuCharme.</p>
Why RDF store is not included in the types of NoSQL databases
<p>After reading some articles about NoSQL databases, I found that there are 4 types of NoSQL databases and for every type there are NoSQL databases.</p>

<p>I understood that NoSQL is Not Only SQL; it means every database that use other query language, but I am confusing why RDF stores are not with this selection of these types (Key/value, Document, Column and Graph).</p>