diff --git a/mkdocs.yml b/mkdocs.yml
index b87e7c5..39f0927 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -44,10 +44,6 @@ nav:
     - Availability: systems_design/availability.md
     - Fault Tolerance: systems_design/fault-tolerance.md
     - Conclusion: systems_design/conclusion.md
-- Big Data:
-    - Introduction, Overview and Usage: big_data/intro.md
-    - Evolution and Architecture of Hadoop: big_data/evolution.md
-    - Tasks and conclusion: big_data/tasks.md 
 - Security:
     - Introduction: security/intro.md
     - Fundamentals of Security: security/fundamentals.md