diff --git a/modules/typedef.js b/modules/typedef.js
new file mode 100644
index 0000000..61405ce
--- /dev/null
+++ b/modules/typedef.js
@@ -0,0 +1,10 @@
+/** @typedef {Object} userData
+ * @property {string} id
+ * @property {string} user - username
+ * @property {string} password
+ * @property {string} email
+ * @property {string} location
+ * @property {string} profileImg - profile picture
+ * @property {string} profileTxt - profile summary
+ * @property {string} registeredDate
+ */