Knowledge representation and reasoning (KR) is the field of artificial intelligence (AI) dedicated to representing information about the world in a form that a computer system can utilize to solve complex tasks such as diagnosing a medical condition or having a dialog in a natural language. Knowledge representation incorporates findings from psychology about how humans solve problems and represent knowledge in order to design formalisms that will make complex systems easier to design and build. Knowledge representation and reasoning also incorporates findings from logic to automate various kinds of reasoning, such as the application of rules or the relations of sets and subsets.

Apache Jena disaster

Jena and Fuseki are not reliable.

Grakn.ai

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Grakn has something new and exciting but not yet ready for prime time.

Ologs

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On knowledge representation through ontology logs and how it's related to category theory.

Introduction to semantics: JavaScript

This tutorial will walk you through what rdflib.js.

Introduction to semantics: Fuseki

About Apache Fuseki, an open source triple store.

Introduction to semantics: C#

Knowledge representation using C# and dotnet.

Introduction to semantics: SPARQL

SPARQL is pronounced 'sparkle' and stands for Semantic Protocol and RDF Query Language. It looks similar to SQL but also totally different since it has to encompass the non-existing field and table names, yet include named graphs and links attached to links.