diff --git a/IT Sofware Engineering Training/month-01/week-01/day-01/ComputerSystems-Linux-Virtualization.md b/IT Sofware Engineering Training/month-01/week-01/day-01/ComputerSystems-Linux-Virtualization.md
index fdb9735..8824e34 100644
--- a/IT Sofware Engineering Training/month-01/week-01/day-01/ComputerSystems-Linux-Virtualization.md	
+++ b/IT Sofware Engineering Training/month-01/week-01/day-01/ComputerSystems-Linux-Virtualization.md	
@@ -19,8 +19,20 @@
 
 #### **2. Lecture: Computer Systems & Network Fundamentals (9:15 AM – 10:15 AM)**  
 - **Topics Covered:**  
-  - Components of a computer system (CPU, RAM, storage, I/O).  
-  - Basics of networking: IP addresses, DNS, DHCP, and subnets.  
+  - **What is a Computer System?**
+    - **Hardware:**
+      - CPU (Processor): The brain – what it does.
+      - GPU (Specific Processor): The brain – what it does.
+      - RAM (Memory): Short-term storage, faster speed access.
+      - Storage (HDD/SSD): Long-term storage, medium speed access.
+      - Motherboard: The central hub.
+      - Input/Output Devices (Keyboard, Mouse, Monitor, Printer).
+    - **Software:**
+      - Operating System (OS): The manager (Windows, macOS, Linux).
+      - Applications: Programs for specific tasks.
+    
+  - Basics of networking: IP addresses, DNS, DHCP, and subnets.
+    ![OSI vs TCP](<OSI-vs-TCP-medium.png> "OSI Layer vs TCP Layer") 
   - Role of OS in resource management.  
 - **Learning Outcome:** Understand how hardware and software interact in networked environments.  
 
@@ -38,13 +50,23 @@
 
 #### **4. Lecture + Group Activity: Bare Metal vs Virtualization vs Containerization (11:30 AM – 12:30 PM)**  
 - **Topics Covered:**  
-  - **Bare Metal:** Direct hardware access, performance trade-offs.  
-  - **Virtualization:** Hypervisors (Type 1/2), resource allocation.  
-  - **Containerization:** Lightweight, shared kernel (Docker example).  
-- **Group Activity:**  
-  - Debate use cases (e.g., “When would you choose containers over VMs?”).  
+  - **Bare Metal:**
+        - Definition: OS directly on hardware.
+        - Pros: Maximum performance, direct hardware access.
+        - Cons: Resource underutilization, difficult to manage multiple applications, hardware dependency.
+    - **Virtualization:**
+        - Concept: Running multiple virtual machines (VMs) on a single physical host.
+        - Hypervisor (Type 1 vs. Type 2 - focus on Type 2 for VirtualBox): The software that manages VMs.
+        - Pros: Resource isolation, efficient resource utilization, portability, disaster recovery.
+        - Cons: Overhead from hypervisor, slightly lower performance than bare metal.
+        - **Analogy:** An apartment building (bare metal) vs. a shared house with separate rooms (virtualization).
+    - **Containerization (Brief Overview - for context):**
+        - Concept: Lightweight, isolated environments sharing the host OS kernel.
+        - Examples: Docker.
+        - Pros: Even lighter than VMs, faster startup, highly portable.
+        - Cons: Less isolation than VMs, shares host kernel.
+        - **Analogy:** Virtualization is a separate house for each family; Containerization is separate apartments within one house.
 
----
 
 #### **5. Lunch Break (12:30 PM – 1:30 PM)**  
 
diff --git a/IT Sofware Engineering Training/month-01/week-01/day-01/OSI-vs-TCP-medium.png b/IT Sofware Engineering Training/month-01/week-01/day-01/OSI-vs-TCP-medium.png
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