ICTICT213 Use computer operating systems and hardware

An operating system (OS) is the software that sits between the hardware and everything else. Applications never talk to a graphics chip or a storage controller directly; they ask the OS, and the OS asks the hardware through a driver. That three-layer relationship, application on top of operating system on top of hardware, is the idea the whole unit rests on, so it is worth being able to draw it from memory.

flowchart TB
  U[User] --> A[Application software<br/>browser, office suite, game]
  A --> OS[Operating system<br/>kernel, services, file system]
  OS --> D[Drivers]
  D --> H[Hardware<br/>CPU, RAM, storage, GPU, NIC, peripherals]
  F[Firmware: UEFI or BIOS] --> H
  F -. starts .-> OS

The jobs a modern OS does fall into a handful of groups:

• Process management and multitasking. The OS shares processor time between programs so you can stream music, browse and edit a document at once.
• Memory management. It hands RAM to programs when they need it and takes it back when they finish, and it moves less-used data out to a page file on disk when RAM runs short.
• Device management. It controls keyboards, displays, printers and storage through drivers.
• File system management. It keeps track of where every file lives and who may open it. Windows uses NTFS, macOS uses APFS, and Linux commonly uses ext4; removable drives often use exFAT so that every system can read them.
• Security. User sign-in, permissions, encryption, a firewall and built-in malware protection are now standard OS features rather than add-ons.
• The user interface, either a graphical user interface (GUI) of windows and icons, or a command line interface (CLI) where you type instructions.

The kernel

At the centre of the OS is the kernel, the part that runs with full control of the hardware and decides which program gets the processor and memory next. It is software, stored on the system drive and loaded into RAM at start-up. On Windows the kernel image is ntoskrnl.exe in the Windows system folder; on Linux it lives in /boot; on macOS it sits inside the protected system volume.

Kernels are usually described in three designs. A monolithic kernel keeps everything, including drivers and file systems, in one large program (Linux is the standard example). A microkernel keeps only the essentials in the core and runs other services separately, which is more robust but slower. A hybrid kernel mixes the two; Windows and macOS both describe their kernels this way.

To see the version you are running:

• Windows: press Windows + R, type winver and press Enter, or open Settings, System, About.
• Linux: open a terminal and run uname -r.
• macOS: open Terminal and run uname -a.

Why does a Certificate II unit bother with history? Because much of today's vocabulary is fossilised from it. We still "patch" software, still talk about "tape backup", still save with an icon of a floppy disk that most students have never held.

The mathematical foundation came from Alan Turing's 1936 paper On Computable Numbers, which described a universal machine able to carry out any calculation given the right instructions. The key insight, that instructions can be stored in memory alongside the data they work on, became the stored-program design that John von Neumann formalised and that every computer since has followed. A machine that can do anything a universal Turing machine can do is called Turing complete, which modern computers are, within the limits of their finite memory.

The first working machines were electromechanical. Konrad Zuse's Z3 of 1941, built from about 2,000 relays, is generally recognised as the first working programmable, fully automatic digital computer; his Z4, delivered to ETH Zurich in 1950, was among the first commercial computers.

Australia has its own place in this story. CSIRAC, built by the Council for Scientific and Industrial Research and first run in 1949, was Australia's first digital computer and the fourth or fifth stored-program computer in the world, depending on how you count. It is the oldest surviving first-generation electronic computer, and it was the first computer to play music. It ran until 1964 and is now on permanent display at Scienceworks in Melbourne, run by Museums Victoria.

Operating systems then passed through recognisable eras:

• Batch processing (1950s and 1960s). Jobs arrived on punched cards and ran one after another. IBM's OS/360 set many of the conventions that followed.
• Time sharing (1960s and 1970s). Many users shared one machine through terminals. UNIX, created at Bell Labs around 1970, came from this era and is the ancestor of Linux, macOS, iOS and Android.
• Personal computers (1980s). MS-DOS put a text-based OS on millions of IBM-compatible PCs.
• Graphical interfaces (1980s and 1990s). The Apple Macintosh and Microsoft Windows made the mouse and the window the default way to use a computer.
• Mobile (2000s and 2010s). iOS and Android were built around touch, sensors, app stores and location.
• Cloud (2010s to now). Services such as Amazon Web Services and Microsoft Azure run operating systems as virtual machines in data centres, and Microsoft's Windows 365 streams a full Windows desktop to any device through a browser.

Did you know? Early programs on punched cards were fixed by physically covering the wrong holes and punching new ones, which is where the term "patching" comes from. The word stayed long after the cards went.

Storage followed a parallel path: punched cards, then magnetic tape (still used today for cheap long-term backup and archiving), then floppy disks (8 inch, then 5.25 inch, then the 3.5 inch 1.44 MB disk), then optical discs and USB flash drives, and now solid-state storage everywhere.

Windows runs most business desktops and laptops. Windows 11 is the current desktop version. Windows 10 reached end of support on 14 October 2025, which matters for anyone still maintaining older machines: they no longer receive security fixes unless enrolled in Microsoft's Extended Security Updates program, which for home users now runs to 12 October 2027. Windows 11 itself is updated through yearly feature releases, each supported for 24 months on Home and Pro editions and 36 months on Enterprise and Education. As at September 2026, version 25H2 (released 30 September 2025) is the mainstream release, 24H2 reaches end of updates for Home and Pro on 13 October 2026, and 26H1 was released in February 2026 for certain new devices only rather than as an upgrade.

macOS runs only on Apple Mac computers. It is known for tight integration with iPhone and iCloud and a strong privacy reputation. It is not sold separately; the cost is built into the hardware, and upgrades are free. Apple moved to year-based version numbers in 2025, so the version number now matches the year after release.

Linux is a free, open-source, Unix-like family of operating systems, released as distributions such as Ubuntu, Fedora, Debian and Linux Mint. It dominates servers, cloud platforms and supercomputers, and it underpins Android. Lightweight distributions such as antiX (which can run in about 256 MB of RAM with around 5 GB of storage) keep old hardware useful.

Raspberry Pi OS (formerly Raspbian) is the Debian-based Linux distribution made for the Raspberry Pi single-board computer, which is popular in education for coding and electronics projects.

ChromeOS runs Chromebooks and is widely used in schools. Its sibling ChromeOS Flex can be installed on older Windows and Mac hardware.

Mobile and tablet systems are dominated by Android and Apple's iOS and iPadOS. Tablet market share moves year to year between the two; roughly half each is a fair summary of recent years. Smartwatches run cut-down versions of the same systems (Wear OS, watchOS) and are usually tethered to a phone.

Comparing them

When you are asked to compare operating systems, compare them on the same few axes every time:

	Windows 11	macOS	Linux (e.g. Ubuntu)
Typical use	Business desktops, gaming, general use	Creative work, Apple ecosystem users	Servers, cloud, development, older hardware
Cost model	Licence per device (often included with a new PC)	Included with Apple hardware	Usually free; paid support available
Hardware	Wide range of vendors, x86 and Arm	Apple hardware only	Almost any hardware
Software compatibility	Largest range of business software	Strong for creative software; some business gaps	Strong for open-source and server tools; limited commercial desktop software
Management at scale	Microsoft Intune, Group Policy	Apple Business Manager and mobile device management	Configuration tools such as Ansible

Files themselves are mostly portable now. A Word document or a PDF opens on all three; what does not move between systems is the executable software. A Windows .exe installer will not run on a Mac, and a macOS app will not run on Windows.

Why organisations standardise

A useful exam of your understanding is to ask what goes wrong if everyone in an organisation chooses their own hardware and software. The answer is a long list: technicians cannot be expert in everything; security becomes uneven because some devices are weaker than others; licences multiply; file compatibility and support contacts fragment; uncommon faults become hard to diagnose; training costs rise; bulk purchasing discounts disappear. This is why organisations publish a standard operating environment (SOE) and approved hardware lists, and why "organisational requirements and specifications" appear all through this unit.

A networked workplace, where computers sign in to central services, adds more benefits: shared printers and files, central updates and security, backups run once for everyone, and staff able to work from anywhere. Today that "network operating system" role is increasingly played by cloud identity and management services (Microsoft Entra ID and Intune, or Google Workspace) rather than a server in the back room, but the reasoning is the same.

You should be able to name the internal and external components of a PC and say what each one does.

Inside the case:

• Motherboard. The main circuit board that everything connects to.
• CPU (processor). Sits in a socket under a heatsink and fan. Intel and AMD dominate desktops; Arm-based chips (Apple silicon, Qualcomm Snapdragon) now appear in many laptops.
• RAM. Plugs into DIMM slots near the CPU. Current desktops use DDR5; many older machines use DDR4. The two are not interchangeable.
• Storage. A hard disk drive (HDD), a 2.5 inch SATA solid-state drive (SSD), or an M.2 SSD mounted directly on the motherboard.
• Graphics. Either built into the CPU (integrated) or on a separate graphics card in a PCIe x16 slot.
• Power supply unit (PSU). Converts mains power to the low voltages the components need. Never open one; its capacitors can hold a dangerous charge after it is unplugged.
• Chipset. On older boards you will see two support chips called the northbridge (which linked the CPU to memory and graphics) and the southbridge (which handled slower input and output). From around 2008 to 2011 the northbridge's jobs moved inside the CPU, and modern boards have a single chipset chip (Intel calls it the Platform Controller Hub). So you will find a northbridge on an older lab PC, but not on a new build.
• CMOS battery. A coin cell that keeps the firmware clock and settings alive when the machine is unplugged.

On the back panel and outside: USB ports, display outputs (VGA and DVI on older machines, HDMI and DisplayPort on current ones), an RJ45 network port, audio jacks, and the peripherals themselves: monitor, keyboard, mouse, external storage, tablets and printers.

Storage in more depth

A hard disk drive stores data magnetically on spinning platters. Read/write heads on an actuator arm float just above the surface and read tiny magnetised regions arranged in concentric tracks, which are divided into sectors. Desktop drives are 3.5 inch; laptop drives are 2.5 inch.

A solid-state drive stores data in NAND flash memory with no moving parts, so it is faster, quieter, more shock-resistant and uses less power. A 2.5 inch SATA SSD connects with a SATA data cable and a power cable and tops out at around 550 MB/s, the limit of the SATA interface. An M.2 SSD is a small stick that screws directly onto the motherboard. It may use SATA (same speed) or NVMe over PCIe, which is far faster; PCIe 4.0 drives reach around 7,000 MB/s and PCIe 5.0 drives more than double that. M.2 drives come in lengths such as 2242, 2260 and 2280 (22 mm wide, 80 mm long for the common 2280).

Flash memory keeps its data without power, which is why it is used in USB drives, phones, cameras and SSDs alike.

Bits, bytes and binary

Computers store everything as binary: 1 for on, 0 for off. One binary digit is a bit; eight bits make a byte. An eight-bit byte holds values from 0 to 255, using place values of 128, 64, 32, 16, 8, 4, 2 and 1. To write 100 in binary, work from the left: 128 does not fit (0); 64 fits (1, leaving 36); 32 fits (1, leaving 4); 16 and 8 do not (0, 0); 4 fits (1, leaving 0); 2 and 1 do not (0, 0). So 100 is 01100100.

Hexadecimal (base 16) uses 0 to 9 and A to F, and is shorthand for binary: one hex digit stands for exactly four bits. You will see it in MAC addresses and colour codes.

Storage units cause real confusion because two systems are in use. Drive manufacturers use decimal (SI) units, where 1 GB is 1,000,000,000 bytes. Windows reports sizes in binary units, where the true names are kibibyte (KiB, 1,024 bytes), mebibyte (MiB) and gibibyte (GiB, 1,073,741,824 bytes), even though Windows labels them KB, MB and GB. That is why a "1 TB" drive shows as about 931 GB in Windows; nothing is missing. The official prefixes run kilo, mega, giga, tera, peta, exa, zetta, yotta, and since 2022 ronna and quetta. Tables online that list "xenottabytes" and similar are invented names, not standards.

Firmware is software stored on a chip inside a device that controls how the hardware starts and behaves. The firmware on a PC motherboard is the first code to run when you press the power button, and it prepares the machine for the operating system.

The older firmware standard was BIOS (Basic Input/Output System). Its replacement, UEFI (Unified Extensible Firmware Interface), is now universal on new PCs, though people still say "the BIOS" out of habit. Windows 11 requires UEFI with Secure Boot capability.

	Legacy BIOS	UEFI
Interface	Text, keyboard only	Often graphical, mouse supported
Disk partitioning	MBR, limited to 2 TB boot disks	GPT, supports very large disks
Start-up	Slower, sequential	Faster
Security	Basic passwords	Secure Boot, which checks that boot software is signed and trusted
Extensibility	Limited	Modular, easier to update

What happens when you press the power button

flowchart LR
  P[Power on] --> F[UEFI/BIOS firmware runs]
  F --> POST[POST: power-on self-test<br/>CPU, RAM, storage, video]
  POST -->|fault| B[Beep codes or error LEDs]
  POST -->|pass| BO[Check boot order]
  BO --> BL[Boot loader on the chosen drive]
  BL --> SB{Secure Boot check}
  SB --> K[Kernel loads into RAM]
  K --> DR[Drivers and services start]
  DR --> L[Sign-in screen]

• The firmware runs the POST (power-on self-test), checking the CPU, memory, storage and video. If something essential fails, you get beep codes or diagnostic lights rather than a picture.
• It then works through the boot order, the ordered list of devices it checks for an operating system (internal SSD, USB stick, network).
• It hands over to the boot loader on the chosen device. With Secure Boot on, UEFI checks the boot loader's digital signature first, which blocks boot-level malware.
• The boot loader loads the kernel into RAM, the kernel starts drivers and services, and you reach the sign-in screen.

A current wrinkle worth knowing: the Microsoft Secure Boot certificates issued in 2011, which are built into the firmware of most PCs, began expiring in June 2026. Microsoft has been rolling out replacement 2023 certificates through Windows Update and firmware updates. A PC that never receives them keeps booting, but it stops receiving updates to its boot security components, so firmware updates from the PC maker matter more than they used to.

Getting into the firmware settings

You need the firmware settings to change the boot order (to install an OS from USB), to enable or disable Secure Boot, to turn on the TPM, or to reset defaults.

• At start-up: press the maker's key repeatedly as the logo appears. Common keys are F2 or Delete on custom builds, F10 on HP, F12 or F2 on Dell and Lenovo, and Esc or F12 for a one-time boot menu. Check the manufacturer's documentation for the exact key.
• From Windows 11: Settings, System, Recovery, then beside Advanced startup choose Restart now. After the restart choose Troubleshoot, Advanced options, UEFI Firmware Settings, Restart. (Older guides for Windows 10 say "Update & Security, Recovery"; the menu moved in Windows 11.)
• From a command prompt run as administrator: shutdown /r /fw /t 0 restarts straight into firmware settings.

A driver is a small piece of software that lets the operating system talk to a particular piece of hardware. It translates general OS instructions into commands that specific device understands, and passes information back. Without the right driver a device may work poorly, only in a basic mode, or not at all.

A printer is the classic example. Windows has no built-in knowledge of the paper trays, duplex unit or ink levels of your particular model; the driver supplies that.

The core drivers for a freshly installed PC, usually installed in this order:

• Chipset drivers, so the OS can manage the motherboard, CPU power states, PCIe lanes and USB controllers.
• Storage, RAID or NVMe drivers, if the installer did not already provide them.
• Network drivers, Ethernet and Wi-Fi, which you want early so the machine can fetch everything else.
• Graphics drivers from Intel, AMD or NVIDIA for correct resolution and performance.
• Audio drivers for the onboard sound chip.

Windows Update supplies many of these automatically, but for best results you identify the exact PC or motherboard model and download from the manufacturer's support site.

Finding and installing the right driver

• Identify the model. For a branded PC, look for the model or service tag on a sticker, or run msinfo32 (System Information) and read System Model and BaseBoard Product.
• Go only to the official support site: the PC maker (Dell, HP, Lenovo, ASUS, Acer), the motherboard maker, or the chip maker (Intel, AMD, NVIDIA). Third-party "driver updater" utilities and look-alike download sites are a common source of bundled adware and malware.
• Match the driver to your exact model and your operating system version.
• Run the installer, and restart when asked.

Working in Device Manager

Device Manager is where you inspect and manage drivers. Right-click Start and choose Device Manager (or run devmgmt.msc).

• A yellow warning triangle means a device has a driver problem; an "Unknown device" means no driver is installed.
• To see a driver's version: right-click the device, Properties, Driver tab. Driver Provider, Driver Date and Driver Version are listed there.
• To update a driver: right-click the device, Update driver, then either Search automatically for drivers or Browse my computer for drivers (if you have already downloaded it).
• If a new driver causes trouble: Properties, Driver tab, Roll Back Driver.
• Windows Update also offers drivers: Settings, Windows Update, Advanced options, Optional updates, Driver updates.

To confirm a graphics driver is working, check Display adapters shows the real GPU name (not "Microsoft Basic Display Adapter") and that Settings, System, Display offers the monitor's native resolution.

A clean install of Windows 11 on a lab PC follows a predictable sequence. The same planning logic applies to any OS.

flowchart LR
  A[Check the PC works<br/>and meets requirements] --> B[Back up data]
  B --> C[Create USB installer]
  C --> D[Boot from USB<br/>via boot menu or boot order]
  D --> E[Install OS]
  E --> F[Drivers and updates]
  F --> G[Apps and security]
  G --> H[Test, restore data, document]

• Check the machine first. Make sure it powers on and the keyboard, mouse and USB ports work, and note the RAM and storage. Confirm it meets the Windows 11 minimums: a compatible 64-bit processor at 1 GHz or faster with two or more cores, 4 GB RAM, 64 GB storage, UEFI with Secure Boot capability, TPM 2.0, a DirectX 12 compatible graphics adapter, and a 720p display larger than 9 inches. The PC Health Check app will tell you whether a machine qualifies.
• Back up anything needed to a USB drive or network location, and confirm the copy opened before you continue.
• Create the installer. On a working PC, download the Windows 11 Media Creation Tool from Microsoft's official download page (microsoft.com/software-download/windows11) and use it to write a bootable USB of at least 8 GB. (Many older guides link the Windows 10 page; Windows 10 is now out of support, so use the Windows 11 page.)
• Boot from the USB. Use the one-time boot menu key, or enter firmware settings and move the USB to the top of the boot order.
• Install. Choose language, time and keyboard (English (Australia)), enter or skip the product key as your organisation directs, choose Custom install, delete the old partitions on the main drive if instructed, and install to the unallocated space. On Windows 11 Home, Microsoft requires an internet connection and a Microsoft account to finish setup; organisations normally sign in with a work or school account, and Microsoft has been steadily removing the old workarounds for creating a local-only account during setup.
• Install drivers (chipset first, then network, graphics, audio) and run Windows Update until no more updates are offered. Several restarts are normal.
• Install security software and required applications.
• Test: internet access, audio, correct display resolution, every USB port, and that each installed application opens. Clear any Device Manager warnings.
• Restore the backed-up files to the correct folders.
• Document what you did: the OS and version installed, how the installer was made, any firmware changes, drivers installed, and any problems and how you fixed them.

In a workplace of any size, technicians rarely build machines one at a time now. New Windows devices are enrolled with Windows Autopilot and configured over the internet by Microsoft Intune, which applies the organisation's settings, apps and security policies automatically. Hand-building a single PC is still the way to learn what those tools automate.

Planning an upgrade for a client

Upgrading every PC in a small office, say a five-person accounting firm, is a small project, and it should be planned as one:

• Confirm the scope and goal with the client in writing.
• Inventory each computer: current OS, hardware specifications and installed applications, especially line-of-business software such as the accounting package.
• Check compatibility against the new OS's minimum requirements and the software vendors' support statements, and identify machines that need upgrading or replacing.
• Back up all data and verify the backups.
• Schedule the work for the least disruption, after hours, on a weekend, or one machine at a time, and avoid the busy end of financial year and BAS deadlines for an accounting client.
• Tell staff what will happen, when, and what will look different afterwards.
• Pilot on one machine first, and test every application, printer and network share on it.
• Have a rollback plan if something fails.
• Upgrade the remaining machines, install drivers, and test each one.
• Support staff for the first days after the change.
• Document the result and get the client's feedback and sign-off.

That last step matters. The unit expects you to seek feedback from the people you did the work for and to confirm that everything asked of you was done.

Software and games publish two sets of requirements. The minimum specification is the least capable hardware the vendor says will run the product at all, usually at the lowest settings, often measured on a clean test machine with nothing else running. The recommended specification is what the product needs to run as designed, with its features at their intended settings. Minimums have a marketing element (nobody wants to rule out customers), so treat them as a floor, not a target.

A worked contrast: Windows 11 needs at least 4 GB of RAM, 64 GB of storage and TPM 2.0 on a supported processor, while antiX Linux runs in a fraction of that on processors a quarter of a century old. For an old computer with limited resources, a lightweight Linux distribution is the practical choice, and ChromeOS Flex is another option; forcing Windows 11 onto unsupported hardware is possible with workarounds, but Microsoft does not support it and it may not receive updates.

Microsoft now also has a higher tier for artificial intelligence features: Copilot+ PCs, which need a neural processing unit (NPU) rated at 40 or more TOPS and at least 16 GB of RAM to run some AI features on the device. AI is becoming a hardware requirement, not just a software one, which is worth remembering when specifying machines that are meant to last several years.

Every technician needs to be comfortable at the command line, because it is faster for many diagnostic jobs and because remote support often means a text session only. Windows 11 opens Command Prompt and PowerShell inside Windows Terminal; press Windows + X and choose Terminal, or search for cmd. Run it as administrator for commands that change the system.

The commands to know by heart:

Command	What it does
ping cdu.edu.au	Sends test packets to a host and reports replies and round-trip time
ping -4 cdu.edu.au	Forces IPv4
ping -t 192.168.1.1	Pings continuously until you press Ctrl + C
ipconfig	Shows the IPv4 address, IPv6 address, subnet mask and default gateway
ipconfig /all	Adds the MAC address, DHCP server, lease times and DNS servers
ipconfig /release then ipconfig /renew	Drops and requests a new DHCP address
tracert cdu.edu.au	Shows each router hop on the way to a host
nslookup cdu.edu.au	Asks DNS for the address of a name
winver or ver	Shows the Windows version and build
systeminfo	Shows OS, build, install date, RAM and more
msinfo32	Opens System Information (model, BIOS version, components)
tasklist / taskkill /im name.exe	Lists or ends running programs
sfc /scannow	Checks and repairs protected system files
winget upgrade --all	Updates installed applications from the command line

Reading ping output: each "Reply from" line shows the responding address, the time in milliseconds and the TTL; the summary shows packets sent, received and lost. "Request timed out" means no reply arrived. That does not always mean the host is down, because many servers and firewalls deliberately ignore ping, so confirm with a browser or a second test before concluding anything. When you ping a name like cdu.edu.au, the first line also tells you which IP address the name resolved to.

In the ipconfig output, find the section for the adapter you are actually using (Ethernet adapter or Wireless LAN adapter) and read the IPv4 Address line. An address beginning 169.254 means the computer asked for an address and nobody answered, which points to a DHCP or connection problem. The IPv6 addresses appear as "Link-local IPv6 Address" (starting fe80) and, where the network supports it, a global "IPv6 Address".

PowerShell equivalents are worth recognising, since much administration now runs in PowerShell: Test-Connection cdu.edu.au, Get-NetIPAddress, Get-ComputerInfo.

These are the routine configuration and optimisation tasks a support technician does, each with the Windows 11 path.

Change the time zone. Settings, Time & language, Date & time. Turn off Set time zone automatically, then choose (UTC+09:30) Darwin from the Time zone list. Darwin is the right choice for the Northern Territory, including Alice Springs, because the NT does not observe daylight saving; choosing Adelaide would shift the clock by an hour in summer. From the command line: tzutil /s "AUS Central Standard Time", and tzutil /g shows the current zone.

Change the desktop background. Settings, Personalisation, Background, then choose Picture, Solid colour, Slideshow or Windows spotlight.

Create a system restore point. Search Start for "Create a restore point" to open System Properties on the System Protection tab. If protection is off for the system drive, select it, choose Configure, turn on system protection and set a disk space limit. Then choose Create, type a description such as "Before driver update", and confirm. A restore point captures system files, drivers and settings (not your documents), so you can roll back a bad driver or update through System Restore on the same tab. Make one before any significant change.

Modify power options. Settings, System, Power (Power & battery on laptops) sets screen and sleep timeouts and the power mode (best power efficiency, balanced, best performance). The classic Control Panel power plans are still reachable with powercfg.cpl, and powercfg /change monitor-timeout-ac 10 sets the screen to turn off after ten minutes on mains power.

Optimise drives. Search Start for "Defragment and Optimise Drives" (or run dfrgui). The tool shows each drive's media type. For a hard disk drive, Optimise defragments it: it gathers the scattered pieces of files into contiguous runs so the heads move less and reads are faster. For a solid-state drive, Windows does not defragment; Optimise sends the TRIM ("retrim") command instead, telling the SSD which blocks are free so it can manage wear and keep write speed up. So the right advice is: never force a traditional defragmentation onto an SSD with a third-party tool, since it adds writes and gains nothing, but do leave Windows' scheduled optimisation turned on for all drives. From an administrator prompt: defrag C: /A analyses and defrag C: /O runs the correct optimisation for the media type.

Find the exact OS build. winver, or Settings, System, About, which shows Edition, Version (such as 25H2) and OS build. The build number matters when checking whether a specific update is installed or a vendor supports your version.

Manage start-up apps. Task Manager (Ctrl + Shift + Esc), Startup apps tab, or Settings, Apps, Startup. Disabling unneeded start-up apps is the quickest boot-time improvement on most machines.

Customise the command line. Windows Terminal settings let you set the default profile (PowerShell or Command Prompt), colour scheme and font; in a classic console window, right-click the title bar and choose Properties. At the prompt, color 0A changes text colours and title My session renames the window.

Install and remove applications. Install from the vendor's official site, the Microsoft Store, or winget install. Remove through Settings, Apps, Installed apps, the three-dot menu beside the app, Uninstall; or Control Panel, Programs and Features (appwiz.cpl); or winget uninstall.

Security software. Windows 11 includes Microsoft Defender Antivirus, which is on by default. Update definitions through Windows Security, Virus & threat protection, Protection updates, Check for updates; run a Quick, Full or Custom scan from Scan options. If you install a third-party antivirus product such as AVG, Defender steps back into a passive role automatically; never run two real-time antivirus products together, because they conflict and can each flag the other as malicious.

Routine maintenance prevents most of the problems a support desk sees:

• Keep the operating system and applications updated, with automatic updates on. Australia's Essential Eight baseline expects patches for internet-facing applications (browsers, office suites, PDF readers, email, security products) within two weeks of release, and within 48 hours where a vulnerability is critical or already being exploited.
• Keep drivers and firmware current from official sources.
• Back up files and settings regularly to an external drive or cloud storage, and test that restores work.
• Keep antivirus protection running and up to date, with regular scans.
• Remove temporary files and unused programs; Settings, System, Storage, and Storage Sense automate this.
• Watch hardware health. Task Manager's Performance tab shows CPU, memory and disk use; manufacturers' diagnostic utilities test drives and memory; blocked fans and dust cause overheating. In Central Australia, fine red dust is a real enemy of fans and heatsinks, so periodic cleaning belongs on the schedule.
• Review Event Viewer (eventvwr.msc) for recurring warnings and errors.
• Keep recovery options ready: restore points, and a recovery USB made with the Recovery Drive tool.
• Restart regularly so updates finish installing and memory is cleared.

Specifying a machine for a client pulls everything above together. Start from the brief (budget, main uses, existing equipment, how long it needs to last) and then select parts that are compatible with each other: a CPU that fits the motherboard socket, RAM of the generation the board supports, a PSU with enough capacity and the right connectors, a case that fits the board and graphics card, and storage the board can take. PCPartPicker (pcpartpicker.com) checks compatibility automatically and shows prices from Australian retailers.

For a gaming client on a $4,000 budget who wants the fastest frames per second for as long as possible, the priorities would be the graphics card first, then a current-generation CPU, 32 GB of DDR5, a fast NVMe SSD, a quality PSU with headroom, and a monitor whose refresh rate the GPU can actually drive. "Future-proofing" means choosing a platform with an upgrade path (a CPU socket that will take later processors, spare M.2 and RAM slots), not simply buying the most expensive part.

AI now sits inside the operating system itself. Windows 11 ships with Copilot; Copilot+ PCs add on-device features that use the NPU; macOS has Apple Intelligence; and Android and iOS have their own assistants. For a support technician this has three practical consequences.

The first is specification. Some features only work on hardware with an NPU of a given performance and enough RAM, so "will it run the AI features the client expects?" is now a hardware question alongside "will it run Windows 11?".

The second is governance. Assistants that can read screens, files and email raise privacy questions that organisations must decide policy on before the features are switched on, and many organisations manage them centrally through Intune or equivalent tools.

The third is that AI is a useful support tool in its own right. Asking an assistant to explain a cryptic error message, or to suggest a PowerShell command, can save time, but the same caution applies as with any unofficial download: read and understand a command before you run it with administrator rights, and check suggested driver or registry fixes against the vendor's own documentation.

The unit's teaching content is drawn from the CDU material held in the unit folder: the ICTICT213 learning resource page on the CDU student site (last updated 22 July 2026), the ICTICT213 Assessor Guide v4.4 (undated), the unit and assessment requirement documents for ICTICT213 Release 1, and the ICT20120 practical observation checklist (February 2026). The unit is current at training.gov.au (no page date shown). Current-practice material was checked on 20 September 2026 against: Microsoft Learn, Windows 11 release information (page updated 14 September 2026), for version, release and end-of-servicing dates; Microsoft Learn, Windows 11 requirements (page updated 14 July 2026), for minimum hardware and the Home edition account requirement; Microsoft's Windows 10 Consumer Extended Security Updates page (date not shown), for the 14 October 2025 end of support and the ESU end date of 12 October 2027; ASD's Blueprint for Secure Cloud and cyber.gov.au's Essential Eight maturity model changes page (maturity model dated November 2023), for patching timeframes. The CSIRAC, Zuse and Turing history, the Secure Boot certificate expiry, the northbridge integration into CPUs, the SI prefixes adopted in 2022, the Windows 11 menu paths and the Copilot+ PC requirements reflect widely documented industry knowledge and Microsoft product documentation rather than a single dated source.