diff --git a/Databases/MongoDB/Introduction.md b/Databases/MongoDB/Introduction.md
index a691e62..f701ea4 100644
--- a/Databases/MongoDB/Introduction.md
+++ b/Databases/MongoDB/Introduction.md
@@ -1,7 +1,7 @@
 ---
 categories:
   - Databases
-tags: [mongo_db]
+tags: [mongo-db]
 ---
 
 # MongoDB: Introduction
diff --git a/Hardware/Logic_Gates/Logic_gates.md b/Hardware/Logic_Gates/Logic_gates.md
index 9f74a0d..2754af8 100644
--- a/Hardware/Logic_Gates/Logic_gates.md
+++ b/Hardware/Logic_Gates/Logic_gates.md
@@ -3,7 +3,7 @@ categories:
   - Computer_Architecture
   - Electronics
   - Hardware
-tags: [logic_gates, binary]
+tags: [logic-gates, binary]
 ---
 
 # Logic gates
diff --git a/Hardware/Logic_Gates/Nand_gate.md b/Hardware/Logic_Gates/Nand_gate.md
index a9cb2eb..d72b9fe 100644
--- a/Hardware/Logic_Gates/Nand_gate.md
+++ b/Hardware/Logic_Gates/Nand_gate.md
@@ -3,7 +3,7 @@ categories:
   - Computer_Architecture
   - Electronics
   - Hardware
-tags: [logic_gates, binary]
+tags: [logic-gates, binary]
 ---
 
 # NAND gate
diff --git a/Hardware/Logic_Gates/Not_gate.md b/Hardware/Logic_Gates/Not_gate.md
index 76ce4f3..a545fac 100644
--- a/Hardware/Logic_Gates/Not_gate.md
+++ b/Hardware/Logic_Gates/Not_gate.md
@@ -3,7 +3,7 @@ categories:
   - Computer_Architecture
   - Electronics
   - Hardware
-tags: [logic_gates, binary]
+tags: [logic-gates, binary]
 ---
 
 # NOT gate
diff --git a/Hardware/Logic_Gates/Or_gate.md b/Hardware/Logic_Gates/Or_gate.md
index 407c2d8..4d74440 100644
--- a/Hardware/Logic_Gates/Or_gate.md
+++ b/Hardware/Logic_Gates/Or_gate.md
@@ -3,7 +3,7 @@ categories:
   - Computer_Architecture
   - Electronics
   - Hardware
-tags: [logic_gates, binary]
+tags: [logic-gates, binary]
 ---
 
 # OR gate
diff --git a/Hardware/Logic_Gates/Xor_gate.md b/Hardware/Logic_Gates/Xor_gate.md
index c9664ec..2f5e497 100644
--- a/Hardware/Logic_Gates/Xor_gate.md
+++ b/Hardware/Logic_Gates/Xor_gate.md
@@ -3,7 +3,7 @@ categories:
   - Computer_Architecture
   - Electronics
   - Hardware
-tags: [logic_gates, binary]
+tags: [logic-gates, binary]
 ---
 
 # XOR gate
diff --git a/Linux/Procedural/User_management.md b/Linux/Procedural/User_management.md
index 872910d..4e419dd 100644
--- a/Linux/Procedural/User_management.md
+++ b/Linux/Procedural/User_management.md
@@ -1,7 +1,7 @@
 ---
 categories:
   - Linux 
-tags: [user_management]
+tags: [user-management]
 ---
 # User management
 
diff --git a/Linux/systemd.md b/Linux/systemd.md
index d057888..b3268c8 100644
--- a/Linux/systemd.md
+++ b/Linux/systemd.md
@@ -1,7 +1,7 @@
 ---
 categories:
   - Linux 
-tags: [systems_programming, systemd]
+tags: [systems-programming, systemd]
 ---
 
 
diff --git a/Mathematics/Algebra/Algebra_key_terms.md b/Mathematics/Algebra/Algebra_key_terms.md
index de3e6c9..15038b8 100644
--- a/Mathematics/Algebra/Algebra_key_terms.md
+++ b/Mathematics/Algebra/Algebra_key_terms.md
@@ -1,7 +1,7 @@
 ---
 categories:
   - Mathematics 
-tags: [algebra, abracadabra]
+tags: [algebra]
 ---
 
 * **Variable**