**6. WebVOWL**

WebVOWL is a web-based ontology visualization open-source tool and is very interactive. This is written by high-level programming language named as Java which implements the visual notation and graphical interface of different nodal points in web ontology language. It explores the creation of ontology and combined forced graph in different formats such as JSON, RDF, and XML and other relevant file formats in an integrated semantic web environment (http://visualdataweb.de/ webvowl/). **Figure 3** represents the WebVOWL interface in semantic web for linking a custom ontology based on URL and URI.

**Figure 2.** *Linked open vocabularies interface in semantic web ontology (https://lov.linkeddata.es/dataset/lov/).*

**Figure 3.**

*WebVOWL interface in semantic environment (http://visualdataweb.de/webvowl/).*
