docs: Add documentation

Author: joachimvh

README.md

@@ -1 +1,35 @@
 # RDF Vocabulary
+
+This library exposes utility functions and types to help working with RDF vocabulary terms.
+
+```ts
+import { createVocabulary } from 'rdf-vocabulary';
+
+// Creates a vocabulary.
+// The first parameter is the namespace, all the following parameters are terms in the namespace.
+const FOAF = createVocabulary(
+  'http://xmlns.com/foaf/0.1/',
+  'Agent',
+  'knows',
+);
+
+// Full term URIs are then accessible through the vocabulary object.
+assert.equal(FOAF.knows, 'http://xmlns.com/foaf/0.1/knows');
+
+// Through the `terms` field, the URIs are exposed as a NamedNode
+assert.equal(FOAF.terms.knows.value, 'http://xmlns.com/foaf/0.1/knows');
+
+// The namespace is accessible in the same way
+assert.equal(FOAF.namespace, 'http://xmlns.com/foaf/0.1/');
+assert.equal(FOAF.terms.namespace.value, 'http://xmlns.com/foaf/0.1/');
+
+// New vocabularies can be created using existing vocabulary object
+const FOAF_EXTENDED = extendVocabulary(FOAF, 'name', 'made');
+assert.equal(FOAF_EXTENDED.name, 'http://xmlns.com/foaf/0.1/name');
+assert.equal(FOAF_EXTENDED.knows, 'http://xmlns.com/foaf/0.1/knows');
+
+// There are several utility types
+const local: VocabularyLocal<typeof FOAF> = 'knows';
+const value: VocabularyValue<typeof FOAF> = 'http://xmlns.com/foaf/0.1/knows';
+const term: VocabularyTerm<typeof FOAF> = namedNode('http://xmlns.com/foaf/0.1/knows');
+```

eslint.config.js

@@ -4,4 +4,7 @@ module.exports = opinionated({
   typescript: {
     tsconfigPath: [ './tsconfig.json', './test/tsconfig.json' ],
   },
+  ignores: [
+    '*.md',
+  ],
 });