The adoption of consistent computer crime or Cyber Crime definitions and a consistent taxonomy is needed in order to assist in the activities like sharing information, reporting and accurate monitoring of computer crime cooperation and collaboration and cooperation on combating computer crime. Finally, the acceptance of common computer crime definitions and a common taxonomy will assist progress in harmonizing computer crime and Cyber Crime regulation and legislation. Therefore, in the current research papers systematic understanding of International Conventions on Cyber Crime and the Challenges of Harmonisationare explained.