CompTIA A+ (Core 1: 220-1201 and Core 2: 220-1202) Flashcards

Core 1 (220-1201) and Core 2 (220-1202). Both must be passed to earn the certification, and they cover complementary domains — hardware/networking versus operating systems/security/operations.

Hardware and network troubleshooting carries the largest weighting in Core 1, reflecting the exam's emphasis on diagnosing and resolving real-world hardware and connectivity issues.

RAM (Random Access Memory) is volatile working memory that loses its contents when power is removed. ROM (Read-Only Memory) is non-volatile and retains firmware or boot instructions even without power.

POST (Power-On Self-Test) is a diagnostic sequence the firmware runs at startup to check core hardware components like RAM, CPU, and video before handing control to the boot loader. Failures are typically reported via beep codes or POST error codes.

UEFI (Unified Extensible Firmware Interface) is the modern firmware standard that supports larger drives, faster boot, Secure Boot, and a graphical pre-boot interface, replacing the older legacy BIOS which used 16-bit code and MBR partitioning.

Secure Boot is a UEFI feature that verifies each boot-stage component is cryptographically signed by a trusted authority before allowing it to execute, preventing rootkits and unsigned bootkits from loading before the OS.

NTFS is a journaling file system used natively by Windows that supports permissions, encryption, and large volumes/files. exFAT is a lighter-weight file system optimized for flash drives and cross-platform compatibility but lacks journaling and native permissions.

A hypervisor creates and manages virtual machines by abstracting and allocating physical hardware resources (CPU, RAM, storage, networking) to each guest OS. Type 1 hypervisors run directly on hardware; Type 2 run atop a host OS.

IaaS (Infrastructure as a Service) provides raw virtualized compute/storage/network. PaaS (Platform as a Service) adds a managed runtime/development environment. SaaS (Software as a Service) delivers a complete, ready-to-use application to end users.

DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses, subnet masks, default gateways, and DNS servers to devices joining a network, eliminating manual configuration.

DNS (Domain Name System) primarily uses port 53 and translates human-readable domain names into IP addresses so devices can locate resources on a network.

TCP (Transmission Control Protocol) is connection-oriented, providing reliable, ordered delivery with error checking and retransmission. UDP (User Datagram Protocol) is connectionless and faster but offers no delivery guarantee, suited to streaming or real-time traffic.

HTTP uses port 80, HTTPS uses port 443, and SSH uses port 22. Knowing these mappings helps technicians troubleshoot firewall rules and service connectivity.

A VLAN (Virtual Local Area Network) logically segments a single physical network into multiple isolated broadcast domains, improving security and traffic management without requiring separate physical switches.

A switch forwards traffic between devices on the same local network segment using MAC addresses. A router forwards traffic between different networks using IP addresses, typically connecting a LAN to the internet or another network.

NAT (Network Address Translation) allows multiple devices on a private network to share a single public IP address by translating private addresses to a public one at the network boundary, conserving public IPv4 addresses and adding a layer of obscurity.

Task Manager gives a quick overview of running processes, apps, and overall resource usage with basic controls to end tasks. Resource Monitor provides deeper, granular detail on CPU, memory, disk, and network activity per process for advanced troubleshooting.

On Windows, ipconfig displays IP configuration details. On Linux and macOS, ifconfig (legacy) or ip addr (modern) serves the equivalent purpose.

chkdsk (Check Disk) scans a storage volume for file system errors and bad sectors, and can attempt to repair logical file system inconsistencies to prevent data corruption or boot failure.

A full backup copies all selected data every time. An incremental backup copies only data changed since the last backup of any type (fastest, smallest). A differential backup copies all data changed since the last full backup (larger than incremental but faster to restore).

Least privilege means granting a user or process only the minimum access rights needed to perform its function, reducing the attack surface and limiting damage from compromised accounts or software.

A virus attaches to a host file and requires user action to spread. A worm self-replicates and spreads across networks without user interaction. A trojan disguises itself as legitimate software to trick users into installing it, with no self-replication.

MFA requires a user to verify identity using two or more independent factors — typically something you know (password), something you have (token or phone), and something you are (biometric) — making unauthorized access significantly harder.

An ACL is a set of rules attached to a resource, such as a router interface or file, that permits or denies specific traffic or users, enforcing granular security policy at that resource.

Social engineering is the manipulation of people, rather than technical exploits, to trick them into divulging confidential information or performing actions that compromise security, such as phishing or pretexting.

A UPS provides short-term battery backup power during outages, protecting connected equipment from data loss and allowing time for a graceful shutdown or transition to another power source.

Change management is a formal, documented process for proposing, reviewing, approving, and implementing changes to IT systems, minimizing risk of disruption and maintaining an audit trail of modifications.

A batch file (.bat) contains simple sequential command-line instructions for Windows cmd. A script, written in languages like PowerShell, Python, or Bash, supports more complex logic such as loops, conditionals, and variables for advanced automation.

Safe Mode starts the operating system with a minimal set of drivers and services, helping technicians isolate whether a problem is caused by third-party software, a driver, or a core OS issue.

A proxy server acts as an intermediary between client devices and the internet, forwarding requests on behalf of clients, which can provide caching, content filtering, anonymization, and centralized access control.