diff --git a/content/notes/03-sequential-logic-circuits.md b/content/notes/03-sequential-logic-circuits.md
new file mode 100644
index 000000000..eba5c77e0
--- /dev/null
+++ b/content/notes/03-sequential-logic-circuits.md
@@ -0,0 +1,15 @@
+---
+title: "03-sequential-logic-circuits"
+aliases: 
+tags: 
+- cosc204
+---
+
+comb log. circuits always produce the same output with the same inputs
+
+Sequential logic circuit output depends not only on the inputs but also past history (memory)
+
+![combinatorial vs sequential](https://i.imgur.com/GbfAZ4c.png)
+
+
+
diff --git a/content/notes/combinatorial-logic-circuit.md b/content/notes/combinatorial-logic-circuit.md
index 9cca08cad..351a15d72 100644
--- a/content/notes/combinatorial-logic-circuit.md
+++ b/content/notes/combinatorial-logic-circuit.md
@@ -1,6 +1,6 @@
 ---
 title: "combinatorial-logic-circuit"
-aliases: logic circuit
+aliases:
 tags: 
 - cosc204
 ---
diff --git a/content/notes/cosc-204.md b/content/notes/cosc-204.md
index 491e9400c..3b644cd27 100644
--- a/content/notes/cosc-204.md
+++ b/content/notes/cosc-204.md
@@ -32,6 +32,8 @@ tags:
 
 # Lectures
 - [01-bits-and-bytes](notes/01-bits-and-bytes.md)
+- [02-combinatorial-logic](notes/02-combinatorial-logic.md)
+- 
 
 
 # Archive