Academic Paper from the year 2020 in the subject Engineering - Communication Technology, , course: PhD-(Electronics and Communication Engineering), language: English, abstract: Interleavers are used in communication system theory for multiple purposes. In this article, an extensive state-of-the-art on theory of interleavers has been presented. It covers the major developments that occurred in the domain of interleaving and interleavers. Fifth generation (5G) communication is a giant leap in cellular communication technologies in terms of data rate, connectivity, quality of services (QoS) and use-cases. The communication theories involved in essence include multiple basic building blocks within the architectural framework. Interleaver and interleaving are two important aspects in this context. It is a fascinating journey how these interleavers have been developed in theory and explored in an unlimited and unexpected way. This article provides a summary of this journey. The only aim is to provide ready references and develop brief understanding of this journey for the researchers who are actively involved in this field.