diff --git a/src/data/roadmaps/javascript/content/undefined@ZLs0NKM0lrnOy5ATDhlk0.md b/src/data/roadmaps/javascript/content/undefined@ZLs0NKM0lrnOy5ATDhlk0.md
index 212c3fa7d..a4e47837d 100644
--- a/src/data/roadmaps/javascript/content/undefined@ZLs0NKM0lrnOy5ATDhlk0.md
+++ b/src/data/roadmaps/javascript/content/undefined@ZLs0NKM0lrnOy5ATDhlk0.md
@@ -1 +1,9 @@
-# undefined
\ No newline at end of file
+# undefined
+
+undefined is a Primitive data type in Javascript.
+
+Whenever a variable is declared but not initialized or assigned a value, then it is stored as undefined. A function returns undefined if a value was not returned. A method or statement also returns undefined if the variable that is being evaluated does not have an assigned value.
+
+Visit the following resources to learn more:
+
+- [@video@undefined in JS](https://www.youtube.com/watch?v=B7iF6G3EyIk&list=PLlasXeu85E9cQ32gLCvAvr9vNaUccPVNP&index=8)