CompTIA A+ is really one certification built from two different exams, and the biggest study mistake is treating them as one blob. Core 1 (220-1201) is about the physical world: hardware, networks, mobile devices, virtualization and troubleshooting them. Core 2 (220-1202) is about what runs on top: operating systems, security, software faults and the procedures of professional support work. This guide walks through all nine domains in plain English, tells you which exam to sit first and why, and turns the whole thing into a week-by-week plan. It contains study guidance and original explanations only - no real or simulated exam questions - and you should always confirm current domains and weights against CompTIA’s official A+ exam objectives before you book.
Chapter 1: Exam overview and how to use this guide
What A+ actually measures
A+ certifies that you can do entry-level IT support: set up, secure and fix the devices, networks and operating systems a help desk deals with daily. The current version, V15, splits this across two exams that you must both pass, on the same version. Core 1 (220-1201) covers five domains: Mobile Devices (13%), Networking (23%), Hardware (25%), Virtualization and Cloud Computing (11%) and Hardware and Network Troubleshooting (28%). Core 2 (220-1202) covers four: Operating Systems (28%), Security (28%), Software Troubleshooting (23%) and Operational Procedures (21%). Each exam runs up to 90 questions in 90 minutes, mixing multiple-choice with drag-and-drop and performance-based questions (PBQs), and each has its own passing score: 675/900 for Core 1 and 700/900 for Core 2.
Which core first, and how far apart
There is no required order, but the sensible default is Core 1 first, Core 2 within a few weeks of it. Three reasons. First, Core 1’s hardware and networking vocabulary underpins Core 2: it is hard to reason about a malware-infected boot sequence or a slow network login if drives, ports and IP settings are still fuzzy. Second, the two exams barely overlap, so studying them strictly in sequence keeps each block coherent instead of diluting both. Third, the same-version rule has teeth: versions retire on a cycle, and a candidate holding one passed core when a version retires has to pair both exams again on the new version. Book Core 2 while your Core 1 pass is fresh. The main exception: if you have spent years in a Windows-admin or security-adjacent role but never touched hardware, starting with Core 2 plays to your strengths and leaves the more foreign material for round two.
How to use this course
Read Chapters 2 to 6 (Core 1) in order, sit Core 1, then read Chapters 7 to 10 (Core 2). Treat the bold terms as a checklist you should be able to explain in one sentence, and pair every chapter with hands-on work: an old desktop you can open, a spare drive to partition, and a free hypervisor running a Windows and a Linux virtual machine cover almost everything. One integrity note: CompTIA prohibits unauthorised training materials, so build your skills from the official objectives, reputable courses and your own lab - not from sites promising shortcuts, which can cost you the certification.
Chapter 2: Core 1 - Mobile Devices (13%)
Laptop hardware you are expected to service
This domain treats a laptop as a repairable machine, not a sealed box. Know the parts a technician actually swaps: SODIMM memory (the small-form-factor module laptops use, as opposed to desktop DIMMs), M.2 and 2.5-inch storage, batteries, keyboards and displays. For screens, know the difference between the panel, the backlight that illuminates it, and the digitizer that senses touch - a faint image you can only see under a torch points at the backlight, while a display that shows a picture but ignores touch points at the digitizer. Expect questions matching a symptom to the failed layer.
Mobile device connectivity and configuration
The rest of the domain is phones and tablets: connection types and when each applies - Bluetooth for pairing peripherals, NFC for tap-range interactions, Wi-Fi versus cellular data for internet, and airplane mode as the master switch that silences every radio at once. Configuration topics include email account setup, synchronisation, and locating a device. The exam angle is almost always practical: which setting explains this symptom, which radio does this task need, what should a technician check when a phone drains its battery while idle (usually a runaway background app, not the SIM).
Chapter 3: Core 1 - Networking (23%)
TCP/IP, ports and protocols
Networking is Core 1’s second-largest domain and the most memorisation-heavy. Start with the transport layer: TCP is connection-oriented and reliable, with acknowledgements and retransmission; UDP is connectionless and fast, used where occasional loss is fine. Then learn the common ports cold - SSH on 22, DNS on 53, HTTP on 80, HTTPS on 443, RDP on 3389, plus the mail trio SMTP/POP3/IMAP - because port questions are quick, certain marks. Round it out with the core services: DHCP hands devices their IP configuration automatically, DNS turns names into addresses, and NAT lets many private addresses share one public one.
Network hardware and Wi-Fi
Know what each box does: a switch connects devices within a network, a router connects networks to each other, an access point gives wireless clients a bridge into the wired network, and a small-office router bundles all three. On the wireless side, understand the trade-off between the 2.4 GHz band (longer reach, more interference, less speed) and 5 GHz and above (faster, shorter range), what an SSID is, and why coverage problems at the far end of a building are fixed by adding or moving access points rather than fiddling with DNS or leases. IP addressing basics complete the picture: private address ranges, the subnet mask that splits network from host, and the default gateway a device uses to leave its own subnet - a machine that reaches local devices but nothing beyond almost always has a gateway problem.
Chapter 4: Core 1 - Hardware (25%)
Components, memory and storage
Hardware is Core 1’s biggest knowledge domain and rewards physical familiarity. Learn the desktop’s cast: motherboard, CPU and its cooler, PSU (which converts wall AC into the regulated DC rails everything runs on), GPU, and the CMOS battery that preserves firmware settings. For memory, distinguish form factors (DIMM desktop, SODIMM laptop) and know that DDR generations are keyed differently and do not interchange. For storage, be able to rank the options: mechanical HDDs are cheap and slow, SATA SSDs much faster, NVMe drives over M.2 faster again because they bypass SATA and speak PCIe directly. RAID turns several drives into one logical volume: RAID 0 stripes for speed with no safety net, RAID 1 mirrors, RAID 5 stripes with parity across three or more drives, RAID 10 mirrors and stripes.
Cables, connectors, printers and peripherals
Connector identification is free marks for anyone who has seen the parts: RJ45 for Ethernet, RJ11 for telephone lines, USB-A/USB-C, HDMI and DisplayPort for video, SATA power and data inside the case. Printers get their own corner of the domain: understand the laser printing process at the level of “toner is fused onto the page by heat”, inkjet and thermal alternatives, and the classic symptom mappings - streaks and faded areas usually implicate the toner or ink path, not connectivity. Finally, know your peripherals and display types well enough to recommend the right part for a described user.
Chapter 5: Core 1 - Virtualization and Cloud Computing (11%)
Virtual machines and hypervisors
The smallest Core 1 domain, and the friendliest to lab practice. A hypervisor is the software layer that runs virtual machines - complete software computers with their own OS - on shared physical hardware. Know why support teams care: VMs isolate risky software in a sandbox, keep legacy applications alive after their hardware dies, and let one test PC host several operating systems. Installing a free hypervisor and building a Windows and a Linux VM is the single highest-value lab task for A+, because it also powers your Core 2 practice.
Cloud models
Cloud questions test two small vocabularies. Service models describe what you rent: IaaS gives raw infrastructure (VMs, storage, networks) you configure yourself, PaaS gives a managed platform you deploy code onto, SaaS gives a finished application. Deployment models describe who it is for: public cloud shared among customers, private cloud dedicated to one organisation, hybrid mixing the two - the classic scenario is sensitive workloads kept private while peak demand bursts to public capacity. Add the cloud characteristics (shared resources, metered pay-per-use, rapid elasticity) and you have the domain.
Chapter 6: Core 1 - Hardware and Network Troubleshooting (28%)
The methodology is the marks
This is the largest domain on Core 1, and a big share of its questions hinge on one thing: the CompTIA troubleshooting methodology, in order. Identify the problem (question the user, check what changed); establish a theory of probable cause; test the theory; establish and implement a plan of action; verify full system functionality and apply preventive measures; document findings, actions and outcomes. The exam loves “what should the technician do next?” - and the answer is almost always the next step of the methodology, not the cleverest fix. Internalise the order until it is reflexive.
Reading symptoms like a technician
The rest of the domain is symptom-to-cause mapping. Hardware: a machine that powers on but shows nothing while beeping is reporting a POST error - firmware caught a hardware fault before the OS ever loaded; intermittent reboots in a dust-choked case point at overheating; clicking drives and S.M.A.R.T. warnings mean imminent storage failure. Network: no connectivity, intermittent connectivity and slow throughput each have their usual suspects, and simple tools carry you far - ping answers “can I reach that host at all?” before any deeper diagnosis. Printers: streaks, ghosting and paper jams each implicate specific parts of the print path. Practise by verbalising the chain: symptom, most likely cause, cheapest test.
Chapter 7: Core 2 - Operating Systems (28%)
Windows administration, tool by tool
Core 2’s biggest domain is mostly “which tool for which job” in Windows. Task Manager shows live processes, performance and startup items; Event Viewer holds the logs you check after crashes and errors; Device Manager manages hardware and drivers; Disk Management creates, formats and resizes partitions. Know the file systems: NTFS is the Windows standard with permissions and encryption support, FAT32 and exFAT are the interchange formats for removable media. Add user-account management, Windows editions at the level of “Pro adds BitLocker and domain join”, installation and upgrade paths, and enough command line to recognise what ipconfig, ping and chkdsk are for.
macOS and Linux basics
The domain also expects working literacy in the other desktop systems. For macOS: Time Machine for backups, Keychain for stored credentials, Spotlight for search, and the general pattern of system settings. For Linux: the concept of distributions, file permissions, and the everyday commands at recognition level - ls, cp, mv, sudo, apt or similar package managers. You are not expected to administer these systems, only to avoid being helpless in front of them, which is exactly the reality of a mixed-fleet help desk.
Chapter 8: Core 2 - Security (28%)
Threats and the malware-removal sequence
Security ties Operating Systems as Core 2’s biggest domain. Know the malware families by behaviour - viruses attach to files, trojans masquerade as legitimate software, ransomware encrypts data and demands payment, spyware and keyloggers watch, rootkits hide - and the social-engineering attacks that skip technology entirely: phishing and its variants, shoulder surfing, tailgating. Then learn the malware-removal sequence as an ordered procedure, because the exam tests the order: identify and research the symptoms; quarantine the infected system; disable System Restore; remediate (update anti-malware, scan, remove); schedule scans and run updates; re-enable System Restore and create a restore point; educate the end user. Isolation comes early so the infection cannot spread; education comes last so it does not happen again.
Hardening, authentication and data protection
The defensive half is a toolkit of small, layered measures. Authentication: strong passwords, MFA so a stolen password alone is not enough, screen locks on every device. Least privilege: users run as standard accounts, UAC prompts before system-level changes, admin rights are the exception. Device hardening: patching, host firewalls, disabling unused features and AutoRun. Wireless: WPA3 (or WPA2 where WPA3 is unavailable) - never WEP, and never mistake MAC filtering for security. Round it out with BitLocker-style disk encryption, physical security basics (locks, badges, privacy screens), and proper data destruction before equipment leaves the building.
Chapter 9: Core 2 - Software Troubleshooting (23%)
Windows symptoms and proportionate fixes
Software troubleshooting rewards one instinct: start with the least invasive fix that matches the scope of the fault. An application that crashes on launch gets repaired or reinstalled before anyone reimages the machine. A PC that blue-screens after a driver update boots into Safe Mode - Windows with minimal drivers - to roll the driver back. “Operating system not found” at power-on sends you to firmware first: is the drive detected, is the boot order right, is a USB stick plugged in? Sluggishness plus pop-up ads with no browser open says adware, which routes you into the malware-removal sequence from Chapter 8 rather than performance tuning.
Mobile and browser symptoms
The same logic extends to phones and browsers. A mobile app that freezes after an update gets force-stopped and its cache cleared before anyone factory-resets the device. Browser redirects, changed home pages and rogue notifications point at unwanted extensions or PUPs - remove them and rescan. The exam’s recurring question shape is “what should the technician try first?”, and the answer is the cheapest, most reversible step that addresses the actual scope of the problem.
Chapter 10: Core 2 - Operational Procedures (21%)
Safety, documentation and change management
This domain is easy to dismiss and easy to pass with modest effort - about a fifth of Core 2 for material with almost no technical difficulty. Physical safety: disconnect power before opening a case, and ground yourself against ESD with a wrist strap, because static that you cannot feel can still kill a component. Professional practice: ticketing systems, clear documentation of what you did and why, knowledge-base articles, and asset management. Change management formalises caution: a documented request, an approval, a tested plan, and a rollback plan so a failed change can be reversed to a known-good state quickly.
Incidents, privacy and professionalism
When a technician finds something serious - a breach, prohibited content - the procedure is to report through the proper channel and preserve the evidence with a documented chain of custody, not to delete, investigate solo or confront anyone. Privacy topics cover PII handling and the point of an acceptable use policy. Backup concepts (full, incremental, differential; test your restores) and basic scripting and remote-access awareness complete the domain. Finally, the soft-skills content is genuinely examined: set expectations, avoid jargon with users, and follow up - the exam treats professionalism as a competency, not decoration.
Chapter 11: Study plan, PBQs and exam day
Sequence the project, then pace each half
Plan A+ as one project with two milestones. A balanced default is ten weeks: six on Core 1 (weight the time toward Hardware, Networking and Troubleshooting, which together are three quarters of that exam), sit Core 1, then four on Core 2 (Operating Systems and Security carry more than half of it), and sit Core 2 while momentum holds. Experienced support staff can compress to six weeks total; complete beginners should stretch toward sixteen and spend the extra time in the hardware lab. Whatever the pace, keep the gap between the two sittings short - the same-version rule makes a stranded single pass expensive. To turn your chosen timeline into dated weeks, use the free study-plan generator.
Practise the PBQs deliberately
Both cores open with performance-based questions, and they are where unprepared candidates burn their clock. Prepare them on purpose: physically install RAM and a drive, partition and format it in Disk Management, build the two VMs, walk the malware-removal order out loud, and drill the troubleshooting methodology until “what comes next?” answers itself. On the day: up to 90 questions in 90 minutes per exam at a Pearson VUE centre or via OnVUE online proctoring. The winning tactic is flag and return - if a PBQ stalls you, mark it, harvest the faster multiple-choice marks, and come back. If you test online, run the system check beforehand and clear your desk.
After A+
A+ opens the door to first-line support; the classic ladder continues with Network+ and then Security+ as you specialise. If you are weighing that next step already, the Security+ vs Network+ comparison lays out which fits which goal - and if you came to A+ with real IT experience, it is worth asking whether you should start there directly.