Update CONTRIBUTING.md

CONTRIBUTING.md

@@ -124,6 +124,15 @@ You start off with the main branch, then a developer creates a feature branch di
 After the feature is developed the code is reviewed and tested on the branch.
 Only after the code is stable it can be merged to main.
 
+* Main dev work is done on feature branches
+* Branches must be prefixed according to their nature:
+** feature/* - for implementing user stories
+** fix/* - for fixing bugs that appeared in the main branch
+** chore/* - any small change without any impact
+* Branch Name:
+** MUST contain : Issue ID in the format #XXX
+** MUST contain: Subject of issue (Abbreviation of pbi summary without using spaces / use "-" to connect) 
+
 <img src="https://raw.githubusercontent.com/eclipse-tractusx/traceability-foss/main/docs/images/github-flow-branching-model.jpeg" height="60%" width="60%"/>
 
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