Task Linking is about establishing meaningful associations between tasks of a project in order to provide an easier reference between related tasks.
There are 3 kinds of links that can be defined and these are;
Related to: If a task is related to the current task, then you can select Related to in order to indicate that the 2 tasks are related.
Duplicated by: If the similar type of task is added before, then you can use Duplicated by in order to link the tasks.
Derived from: If the current task is the result of or derived from a previous task, then you can use Derived from to link the task.

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In Orangescrum Project Management tool, Task Linking can be done upon task create, task edit, and task details.
Note – Here, you’ll get 3 options such as Related to, Duplicated by & Derived from.