This section explains how mobile devices use rechargeable batteries and

discusses important factors, like battery lifespan and safe handling

practices, to keep in mind.

Mobile Device Power

 Unlike devices that rely on constant power from outlets, mobile

technology utilizes rechargeable batteries for portability.

 These batteries can be charged using various methods, including

external chargers, cradle stands, and wireless charging pads.

Battery Lifespan and Safety

 Rechargeable batteries have a limited lifespan, measured in charge

cycles, and their performance can decline over time.

 It's crucial to handle batteries safely, as damaged batteries can

pose risks such as swelling, rupturing, or even catching fire.

IT Support and Battery Issues

 IT support specialists often troubleshoot battery and charging

issues, ensuring compatibility between chargers, batteries, and
devices.

 They may also receive training on battery replacement or be

responsible for sending devices for repair.

Peripherals and USB Connections

 Peripherals are external devices connected to a computer for added

functionality, with USB devices being the most common type.

 USB comes in various versions, with USB 2.0, 3.0, and 3.1 being the
most prevalent today, each offering different transfer speeds.

Understanding Data Transfer Rates

 It's important to differentiate between megabytes (MB) for storage

and megabits per second (Mb/s) for transfer speed.

 For instance, transferring a 1MB file in a second requires an 8 Mb/s

connection speed.

Display Peripherals and Standards

 Common display connectors include DVI, HDMI, and DisplayPort,

each with its capabilities.
  While DVI primarily handles video output, HDMI and DisplayPort
support both audio and video transmission.

USB Connectors

 USB connectors are essential for data transfer and powering

devices. Different generations like USB 2.0, 3.0, and 3.1 offer
varying speeds, with newer versions providing faster data transfer
rates.

 Smaller connectors like Micro USB, USB-C, and Lightning Ports cater
to portable devices, offering faster speeds and greater power
capabilities compared to older USB types.

Communication Connectors

 RJ-11 connectors are used for POTS (Plain Old Telephone Service)
transmitting voice data.

 RJ-45 connectors, primarily used with ethernet cables, connect

computers to networks, while F-type connectors are common for
cable modems.

Legacy Connectors

 DB89 connectors, used for older peripherals like keyboards and

mice, might still be encountered.

 Molex connectors, commonly used for powering internal devices like

hard drives and disc drives, are also important to recognize.

Connecting Devices

 Drivers act as translators, allowing the CPU to understand and

interact with external devices like keyboards and printers.

 The BIOS (Basic Input Output Services) is the initial software that
prepares the hardware and loads the operating system.

BIOS and Boot Process

 The BIOS resides in the ROM (Read Only Memory) chip on the
motherboard, ensuring it's available even when the computer is off.
  UEFI (Unified Extensible Firmware Interface), a modern replacement
for BIOS, offers better compatibility with newer hardware.

Troubleshooting and BIOS Settings

 The POST (Power-On Self-Test), run by the BIOS, checks the

hardware during boot-up, indicated by beeps for errors.

 The CMOS chip stores boot settings like date, time, and boot order,
which can be modified in the BIOS settings menu.

Protecting Your Components

 Electrostatic discharge (ESD) can damage computer components, so

it's crucial to take precautions. You can ground yourself by touching
a plugged-in (but not powered on) electrical device or by wearing an
anti-static wrist strap.

 Remember that computer parts often come in anti-static bags for

protection, so keep them inside until you're ready to install them.

Motherboard and CPU Installation

 The motherboard is the foundation of your computer. Ensure your

chosen motherboard fits your computer case's form factor.

 The CPU is the brain of your computer. Carefully align the CPU with
the socket on the motherboard, ensuring the markers match. Secure
it in place with the lever arm.

Cooling the CPU

 A heat sink is vital for dissipating heat from the CPU. Before
attaching it, apply thermal paste evenly to the CPU's surface to
improve heat transfer.

 Once the thermal paste is applied, align the heat sink with the CPU
socket and screw it in securely. Remember to connect the heat
sink's fan to the motherboard.

RAM Installation

 Align the RAM sticks with the DIMM slots, ensuring they match
before installation to avoid damaging the pins.

 Use the white DIMM slots and push the RAM until it clicks, indicating
it's securely locked.
Storage and Cooling

 Install the SSD by sliding it into the designated cage in the case and
connecting it to the motherboard using a SATA cable.

 Install the case fan by aligning it with the grooves and attaching it to
the motherboard header labeled "rear fans," ensuring proper airflow.

Power Supply Installation

 Carefully position the power supply in the case, route cables to

avoid obstruction, and secure it with screws.

 Remember that the power supply can be installed before or after the
motherboard depending on the case layout.

Computer Assembly Steps

 The content guides you through connecting essential components

like the motherboard, CPU, RAM, and graphics card.

 It also covers connecting peripherals such as the monitor, keyboard,

and mouse to the assembled computer.

Troubleshooting Tips

 The guide offers advice on troubleshooting common issues, such as

the computer not starting up.

 It suggests checking the power supply wattage and ensuring

connectors are properly seated.

Operating System Installation

 The content highlights the importance of an operating system and

mentions that the next lesson will cover its installation.

 It concludes by emphasizing the accomplishment of building a

functional computer from individual components.

Mobile Device Repair

 Understand your organization's policy on mobile device repair

before attempting any fixes, as you may not be authorized to repair
all devices.
  Repairing a device yourself may void its warranty, so explore
training options and understand the implications for each device.

The RMA Process and Data Security

 Familiarize yourself with the Return Merchandise Authorization

(RMA) process for devices you handle, as it dictates the repair or
replacement procedure.

 Before sending a device for repair, ensure all proprietary or personal

data is removed, potentially through a factory reset, to protect
sensitive information.

Liquid Crystal Displays (LCD)

 Require backlighting: LCDs use liquid crystals that manipulate

light rather than produce it, necessitating a backlight.

 Types of LCDs:

o IPS (In-Plane Switching): Vibrant colors, wide viewing

angles, great for visual tasks, but can be expensive.

o TN (Twisted Nematic): Affordable, fast response times, good

for basic tasks and gaming, but limited viewing angles and
color accuracy.

o VA (Vertical Alignment): Good contrast and black levels,

decent response times, but can suffer from motion blur.

Organic Light Emitting Diodes (OLED)

 Emissive displays: OLEDs use organic materials that emit light

when electricity is applied, eliminating the need for a backlight.

 Advantages: Excellent picture quality, wide viewing angles, infinite

contrast, energy-efficient, and can be made flexible.

 Disadvantages: Susceptible to burn-in, blue LEDs degrade faster,

sensitive to light and moisture.

AMOLED (Active Matrix OLED)

 Enhanced OLED: Uses active matrix technology for faster pixel

control, resulting in better image quality and response times.

 Common in high-end devices: Found in premium smartphones

and monitors due to their superior visual performance.
Mini-LED and Micro-LED

 Next-generation displays: Use even smaller LEDs than OLED,

offering potential for even better brightness, contrast, and energy
efficiency.

 Mini-LED: Primarily used for backlighting in LCDs, improving their

performance.

 Micro-LED: Still under development but holds promise for the

future of displays.

O.S

 What it is: An Operating System (OS) is like the brain of your

computer, managing all software and hardware.

 Key Parts:

o Kernel: The core of the OS, talking directly to hardware and

managing resources.

o User Space: Everything we interact with directly, like

programs and interfaces.

 Main Functions:

o File Management: Organizes and stores data like a filing

cabinet.

o Process Management: Runs and manages programs

efficiently, like a multitasking chef.

o Memory Management: Allocates and optimizes memory

usage for smooth operation.

o I/O Management: Handles communication with external

devices (keyboard, mouse, etc.).

 Before we can even think about storing files, our operating system
needs a way to organize and manage the available space on our
hard disks. This is where file systems come in, acting as the
organizers of our digital world.

 Different operating systems often have their preferred file systems,

each with its own strengths, like NTFS for Windows and EXT4 for
Linux, highlighting the importance of understanding these
 differences, especially in scenarios like data recovery or dual-
booting.

Data Storage: Breaking It Down

 To optimize storage and access speed, our files are rarely stored as
one continuous chunk of data. Instead, they are broken down into
smaller data blocks that can be spread across the hard drive, a
concept known as block storage.

File Metadata: More Than Meets the Eye

 Beyond the actual data, each file carries crucial information known
as metadata. This includes details like creation date, modification
history, access permissions, and even the file type, often indicated
by the file extension, which helps the system (and us!) understand
the nature of the file.

Process Management

 A process is a running program (like a browser or text editor), and

many processes from the same program can run simultaneously
(like multiple Chrome windows).

 The kernel efficiently manages your computer's limited resources

(RAM, CPU) to run multiple processes concurrently.

Time Slices and CPU Allocation

 The kernel allocates time slices, very short intervals, to each

process for CPU execution.

 The CPU rapidly switches between processes, creating the illusion of

simultaneous execution.
 Virtual Memory Explained: Virtual memory combines your hard drive space and RAM
to act as a larger pool of memory for your processes. It's like creating extra workspace
when you don't have enough room on your desk!
 Pages and Swapping: Programs are divided into "pages" and stored in virtual memory.
When needed, these pages are moved to RAM for execution. This process, called
swapping, helps manage even large applications smoothly.

Thinking of virtual memory like a cookbook can be helpful:

 Efficient Memory Use: Just like you wouldn't read an entire cookbook to make one
recipe, your computer doesn't load an entire program into RAM at once. It only accesses
the necessary pages, saving precious RAM.

Swap Space: The area on your hard drive dedicated to storing virtual
memory is called "swap space."
Userspace

 Encompasses how users interact with an operating system,

including actions like creating files, opening applications, and
deleting items.

 Offers two primary interaction methods: shells and graphical user

interfaces (GUIs).

Shells

 Programs that interpret text commands and send them to the OS for
execution.

 Essential for power users and in Linux environments, especially for

remote access and managing multiple machines.

 Bash (Bourne Again Shell) is a common and widely used shell.

Graphical User Interfaces (GUIs)

 Provide a visual way to interact with computers, using a mouse for

actions like clicking, dragging, and opening folders.

 Recognizable in everyday devices like computers, mobile phones,

tablets, ATMs, and airport kiosks.

 While GUIs offer convenience, understanding shells remains crucial

for IT support roles, as some tasks require command-line
interaction.

 Just like a video game save point helps you restart after
encountering a problem, logs help us understand what went wrong
with our computers.

 Logs record various events like startup processes, driver

installations, and error messages, acting like a computer's diary.

Understanding Logs

 Logs can be difficult to read because they contain a vast amount of

information about everything the computer does.

 By learning to navigate and read logs effectively, we can interpret

the information they hold and solve computer problems.

Powering On and Initializing

 The computer turns on, and a low-level software called BIOS/UEFI

kicks in to make sure all the hardware is working correctly.

 It then runs a self-test (POST) to diagnose any potential issues.

Finding and Loading the Operating System

 The BIOS/UEFI then looks for a bootable device, like your hard drive
or a USB drive, based on the boot order you've set.

 Once it finds a bootloader on one of these devices, it executes the

program to start loading the operating system.

Getting Your Computer Ready to Use

 The bootloader loads the operating system's kernel, which manages

the computer's resources and allows hardware and software to
communicate.

 Finally, essential system processes and user space items are

launched, like the login screen and desktop environment, so you can
start using your computer.

Understanding the Boot Process

 The BIOS/UEFI runs checks on your computer hardware, then

searches for a bootloader on devices in the configured boot order.

 The bootloader, once found, initiates the loading of your chosen

operating system.

Boot Method Options

 You can boot from various devices like USB drives, optical media,
external hard drives, and even over a network.

 Internal options include booting from different partitions on your

hard drive, allowing for dual-booting multiple operating systems.

Configuring Boot Options

 Access the BIOS settings to change the boot order and choose your
preferred boot method.

 This allows you to prioritize different devices or partitions for

booting your computer.

Using external boot options can be really helpful when recovering a

computer that has a corrupted OS. Here are a couple of external
boot options that are commonly used:

 Booting from a USB drive: You would first need to create a

bootable USB drive containing the necessary operating system files.
 Once you have that, you can then configure your BIOS to boot from
the USB drive.

 Booting from an optical media: Similar to the USB method, this

involves using a CD, DVD, or Blu-ray disc with the OS installation
files on it. You would need to change the boot order in your BIOS to
prioritize the optical drive.