Full class notes for A+ Core 1 3.5: choosing between ATX, micro-ATX and Mini-ITX by size, slots, power and mounting.
Lesson Note
#class-notes
91 entries across collections.
Full class notes for A+ Core 1 3.5: buses, PCI vs PCIe, parallel vs serial, PCIe lanes, and installing add-in cards safely.
Lesson Note
Full class notes for A+ Core 1 3.5: main and PCIe power connectors, SATA/eSATA data, front-panel and USB/TPM headers, and M.2.
Lesson Note
Full class notes for A+ Core 1 3.5: Intel vs AMD sockets, installing a CPU, and multisocket server motherboards.
Lesson Note
Full class notes for A+ Core 1 3.5: BIOS firmware, POST and boot, legacy BIOS vs UEFI, dual-BIOS flash, and settings.
Lesson Note
Full class notes for A+ Core 1 3.5: entering setup, boot order, USB control, fan and temperature, Secure Boot, passwords, CMOS reset and virtualisation.
Lesson Note
Full class notes for A+ Core 1 3.5: protecting cryptographic keys with a TPM (root of trust, BitLocker) and centralising them with an HSM.
Lesson Note
Full class notes for A+ Core 1 3.5: 32-bit vs 64-bit (x86/x64), ARM architecture, and multi-core CPUs.
Lesson Note
Full class notes for A+ Core 1 3.5: sound cards, discrete GPUs, capture cards, NICs, and driver install best practice.
Lesson Note
Full class notes for A+ Core 1 3.5: fans and airflow, passive cooling, heat sinks, thermal paste and pads, and liquid cooling.
Lesson Note
Full class notes for A+ Core 1 3.7: MFD setup, drivers, PCL/PostScript, connectivity, sharing, print features, secure printing, and scanning.
Lesson Note
Full class notes for A+ Core 1 3.8: the laser imaging process, toner/OPC drum, cartridge and maintenance-kit replacement, calibration, and cleaning.
Lesson Note
Full class notes for A+ Core 1 3.8: inkjet operation, CMYK cartridges, print heads, feed rollers, duplex, and (beyond the clip) carriage/belt and calibration.
Lesson Note
Full class notes for A+ Core 1 3.8: cleaning inkjet print heads, replacing CMYK cartridges, calibration, and clearing paper jams.
Lesson Note
Full class notes for A+ Core 1 3.8: how thermal printers work, the feed assembly and heating element, thermal paper care, and handling output.
Lesson Note
Full class notes for A+ Core 1 3.8: replacing thermal paper, cleaning the heating element, removing debris safely, and heat/fade sensitivity.
Lesson Note
Full class notes for A+ Core 1 3.8: dot-matrix print heads, ribbons, tractor-feed paper, and multi-part carbonless copies.
Lesson Note
Full class notes for A+ Core 1 3.8: ribbon replacement, print head replacement, and continuous tractor-feed paper handling on dot-matrix printers.
Lesson Note
Full class notes for TLCL ch. 8: readline cursor movement and editing, cut/paste (kill and yank), tab completion, and command history/expansion.
Lesson Note
Full class notes for TLCL ch. 9: users/groups/other, read/write/execute, chmod, umask, special permissions, su/sudo, chown/chgrp, and passwd.
Lesson Note
Full class notes for Networking for Sysadmins ch. 3: IPv4 addressing, subnets/netmasks, viewing config on Windows/Debian/FreeBSD, private addressing and NAT, and troubleshooting.
Lesson Note
Full class notes for MoL ch. 7: management shells, snap-ins vs modules, module discovery/import, profile scripts, and the PowerShell Gallery.
Lesson Note
Full class notes for MoL ch. 8: what objects are, Get-Member, properties and methods, Sort-Object, Select-Object, and format-last discipline.
Lesson Note
Full class notes for TryHackMe module 6: domain structure (TLD/SLD/subdomain), A/AAAA/CNAME/MX/TXT records, and the DNS resolution journey.
Lesson Note
Full class notes for TryHackMe module 7: HTTP/HTTPS, URL structure, requests and responses, HTTP methods, status codes, headers, and cookies.
Lesson Note
Full class notes for TryHackMe module 8: front end vs back end, HTML/CSS/JS, page source, sensitive data exposure, and HTML injection.
Lesson Note
Full class notes for TryHackMe module 9: load balancers, CDNs, databases, WAFs, web server software, virtual hosts, and static vs dynamic content.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.1: LCD backlights, TN vs IPS vs VA, OLED, mini LED local dimming, touchscreens and digitizers, and inverters.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.1: pixel density and PPI maths, refresh rate and frames per second, resolution and aspect ratio, and colour gamut.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: twisted pair and why it is twisted, cable categories and distances, coax, UTP vs STP shielding codes, direct burial and plenum-rated cable.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: ANSI/TIA-568 and ISO/IEC 11801, the T568A and T568B pinouts, what differs between them, and wiring keystone jacks.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: how light travels through a fibre core and cladding, ferrules and connectors, and multimode versus single-mode fibre.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: USB versions and speeds, USB connector types and USB-C, DB-9 serial and RS-232 console access, and Thunderbolt 1 to 4.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: SATA revisions and speeds, the one-to-one SATA power and data connectors, and eSATA.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: DVI-D to HDMI and DVI-A to VGA compatibility, USB-to-Ethernet and USB-C-to-USB-A adapters, and USB hubs.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: RJ11 and RJ45, F connectors and DOCSIS, punchdown blocks, USB and USB-C, Molex, Lightning, and DB-9/RS-232.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: ST bayonet connectors, SC push-pull connectors, and compact LC connectors for optical fibre.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.3: RAM vs storage, DIMM and SO-DIMM, 64-bit data width, SDRAM, double data rate, and DDR3/DDR4/DDR5 compatibility and keying.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.3: parity memory and even-parity calculation, ECC memory, memory bandwidth in MT/s, and multi-channel RAM.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.4: hard drives and RPM, SSDs, PCIe and NVMe, SAS, mSATA and M.2 keying, flash memory formats, and optical drives.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.4: RAID 0 striping, RAID 1 mirroring, RAID 5 and RAID 6 parity, and nested RAID 1+0.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.6: power supply safety, AC vs DC, amps/volts/watts, regional voltage, the 24-pin connector, redundant PSUs, modular cabling, wattage sizing, and 80 PLUS efficiency.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 3.2: HDMI, DisplayPort and its locking connector, DVI variants and single/dual link, VGA, and video over USB-C.
Lesson Note
Full class notes for TLCL chapter 7: pathname, tilde, arithmetic, parameter and command expansion, then double quotes, single quotes and backslash escaping.
Lesson Note
Full class notes on PowerShell providers and PSDrives: what providers are, filesystem organisation, other data stores as drives, navigation, and wildcards vs literal paths.
Lesson Note
Full class notes on the PowerShell pipeline: connecting commands, exporting to CSV/XML, printing, ConvertTo-Html, system-modifying cmdlets, and common pipeline confusion points.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 2.7: satellite (GEO vs LEO), fibre, cable and DOCSIS, DSL, cellular tethering and hotspots, and WISPs.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 2.8: crimpers, Wi-Fi and spectrum analysers, tone generator and probe, punch-down tools, cable testers, loopback plugs, taps and port mirrors.
Lesson Note
Full class notes for TLCL chapter 6: standard input, output and error, redirecting and combining streams, /dev/null, group commands, pipelines and the filters uniq, wc, grep, head, tail and tee.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 2.5: routers, managed and unmanaged switches, access points, firewalls, PoE and ISP devices.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 2.6: IPv4 structure and binary, RFC 1918 private ranges and NAT, IPv6 notation and /64 prefixes.
Lesson Note
Full class notes for Professor Messer A+ 220-1201 objective 2.6: IP address, subnet mask and gateway; static addressing vs DHCP reservations; APIPA.
Lesson Note
Full class notes for Lucas, Networking for System Administrators (2nd ed.) ch. 1: the four network layers, encapsulation and troubleshooting layer by layer.
Lesson Note
Full class notes for Lucas, Networking for System Administrators (2nd ed.) ch. 2: interfaces, autonegotiation, MTU, ARP and Neighbor Discovery, VLANs and datalink errors.
Lesson Note
Full class notes for TryHackMe Pre Security (2026 path) module 5, What is Networking?: networks and the internet, IP and MAC addresses, and ping.
Lesson Note
Full class notes for TryHackMe Pre Security (2026 path) module 5, Intro to LAN: star, bus and ring topologies, switches and routers, subnetting, ARP and DHCP.
Lesson Note
Full class notes for TryHackMe Pre Security (2026 path) module 5, OSI Model: the seven layers, what each one does, TCP versus UDP, and encapsulation.
Lesson Note
Full class notes for TryHackMe Pre Security (2026 path) module 5, Packets & Frames: packets vs frames, the TCP/IP model, TCP headers and the three-way handshake, UDP and ports.
Lesson Note
Full class notes for TryHackMe Pre Security (2026 path) module 5, Extending Your Network: port forwarding, stateful and stateless firewalls, VPNs, routers, switches and VLANs.
Lesson Note
Exam tip: on the 220-1201 exam, display technologies (LCD, OLED, digitizers, inverters) moved to section 3 (Hardware). Section 1 is laptop hardware, connections and connectivity/management.
Lesson Note
A laptop packs a full computer into a very small space. That's why it's the standard platform for anyone on the move — but it's also why laptops are harder to service:
Lesson Note
Almost everyone in an organisation carries a phone, a tablet or both. Each device needs a way to connect back to computers and networks — and different devices have historically used different connectors and standards.
Lesson Note
Fingers work well for tapping and swiping, but they're imprecise. A digital stylus works like a pen or pencil on the screen, giving much finer, more granular control — for handwriting, drawing, annotating documents…
Lesson Note
An organisation may have hundreds or thousands of phones and tablets. Some are company-owned; others belong to employees. They're outside the office, easily lost, and each needs the right apps, email settings and…
Lesson Note
Data sent across a network is wrapped in layers, like envelopes inside envelopes (
Lesson Note
Note: this video doesn't map directly to an exam objective. Messer presents it as a primer: everything in the networking domain builds on it, so it's worth learning well.
Lesson Note
You'll use these port numbers in two everyday situations:
Lesson Note
When people say "wireless networking", they usually mean the network used at home or work to reach other devices and the internet. This is standardised by the IEEE — the Institute of Electrical and Electronics…
Lesson Note
A typical data centre holds rack after rack of equipment, with many different services running across those racks. This lesson works through the services you'd expect to find there — and several you'll meet…
Lesson Note
DNS (Domain Name System) is one of the most critical services on any network. It lets us provide IP addresses when all we remember is a fully qualified domain name (FQDN).
Lesson Note
Before automatic addressing, every device's IP configuration — IP address, subnet mask, default gateway, DNS servers and other settings — had to be entered manually. That was manageable with a small number of devices…
Lesson Note
A LAN (Local Area Network) is a group of devices connected together into a single broadcast domain. Send a broadcast from one device on that LAN, and every other device on that same LAN sees it.
Lesson Note
When you type a command, something has to read it, work out what you mean and ask the operating system to do it. That something is the shell: a program whose whole job is to take keyboard commands and pass them to…
Lesson Note
Linux, like Windows, organises files into a hierarchy of directories (folders) that can contain files and further directories. The first directory is the root directory, written /. Everything else branches out from it.
Lesson Note
Most commands follow the same general shape:
Lesson Note
A graphical file manager is fine for moving one file. But consider this task: copy every HTML file from one directory to another, but only files that don't exist in the destination or are newer than the copies there.…
Lesson Note
When you type a name at the prompt, it can be any one of four things:
Lesson Note
Graphical tools are good for doing one thing, once. They struggle with:
Lesson Note
PowerShell is two things working together:
Lesson Note
PowerShell has thousands of commands, and every module you install adds more. No one memorises them. Skilled PowerShell users are skilled at finding and reading help. The book is emphatic on this point: if you learn…
Lesson Note
Many people avoid PowerShell because they think it means "programming". But most day-to-day PowerShell is simply typing commands and pressing Enter, just as you would in CMD or Bash. A script is only a text file of…
Lesson Note
The Practical Help Desk course takes someone with no IT experience to the point where they can do the real work of a Tier 1 help desk technician. It's also the foundation TCM recommends before its more advanced…
Lesson Note
Information Technology (IT) is the people, processes and technology an organisation uses to create, store, move and protect information. In practice, IT exists to keep the business working. The payroll team needs…
Lesson Note
A computer is built from billions of tiny switches (transistors). A switch has two reliable states: off and on, which we write as 0 and 1.
Lesson Note
Electrostatic discharge (ESD) is the sudden flow of static electricity between two objects at different charge levels. You feel a shock at around 3,000 volts, but chips can be damaged by a few hundred — far below…
Lesson Note
Limited — RAM and storage sometimes; CPU and GPU almost never (soldered)
Lesson Note
An operating system (OS) manages the hardware and gives programs a consistent, safe way to use it. Without an OS, every application would need its own code to drive the disk, network card and screen — and nothing…
Lesson Note
Note: these notes are written from the module's topic outline, not from the rooms themselves. Room names and exercise specifics aren't reproduced — cross-check against the rooms as you work through them.
Lesson Note
Note: rooms in this module include Inside a Computer System and Computer Types. These notes are written from the module outline — cross-check room specifics as you go.
Lesson Note
Note: rooms in this module include Operating Systems: Introduction and Windows Basics, with Linux covered alongside. These notes are written from the module outline — cross-check room specifics as you go.
Lesson Note
Note: these notes are written from the module's topic outline (data representation, Python, JavaScript, databases and SQL). Cross-check room specifics as you go.
Lesson Note