Depending on the method and/or tool used, there are different terms for the same or similar entities. The temptation to use the tool which is currently available is huge. Each additional tool costs not only money to purchase, but also time for the commissioning and maintenance. Requirements, for instance, are managed with Jira or MS TFS and operated with DOORS Scrum, because at first sight an issue in Jira does not differ much from an object in DOORS. Or is it all the same in the end? Are there any significant differences? And if so, what is their nature? Are the differences dependent on situation or task? These and similar questions will be discussed in the presentation using the concepts 'Digital Twin' and 'Digital Thread' while solution concepts will be demonstrated.