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CompTIA A+ Core 1 (220-1201) Glossary

Fuad Efendi March 29, 2026 3 min read

Review the A+ Core 1 terms, abbreviations, and high-confusion pairs that show up across hardware, networking, mobile, and troubleshooting questions.

On this page

Use this glossary for rapid recall, not as your main study method. When a term still feels vague after reading the definition, go back to the relevant lesson page and relearn it in context.

Core terms

TermFast meaningStart here if it still feels fuzzy
APIPAAutomatic private address in the 169.254.0.0/16 range that usually signals a DHCP failure path2.2 Addressing, TCP/IP & SOHO Foundations
BluetoothShort-range wireless technology used for accessories, headsets, keyboards, and tethered peripherals1.2 Mobile Ports, Accessories & Docking
DDRDouble data rate memory generation such as DDR4 or DDR53.1 Motherboards, Firmware, CPUs & Memory
DFU modeDevice Firmware Update mode used for deeper iPhone or iPad recovery1.4 Mobile Device Troubleshooting
DHCPDynamic Host Configuration Protocol, the service that hands out IP settings automatically2.2 Addressing, TCP/IP & SOHO Foundations
DNSDomain Name System, which translates hostnames to IP addresses2.1 Ports, Protocols & Common Services
HypervisorSoftware layer that hosts virtual machines4.1 Virtualization, Hypervisors & Client-Side Labs
M.2Physical form factor used by some SSDs, Wi-Fi cards, and expansion modules3.3 Storage Devices, Interfaces & RAID Basics
NFCNear-field communication, a very short-range wireless technology used for pairing and tap actions1.2 Mobile Ports, Accessories & Docking
NVMeNon-Volatile Memory Express, a high-speed storage protocol usually carried over PCIe3.3 Storage Devices, Interfaces & RAID Basics
PBQPerformance-based question that asks you to apply support logic, not only definitionsFAQ
PoEPower over Ethernet, which sends electrical power over network cabling to devices like APs or cameras2.4 Network Tools, Cabling & Basic Evidence
RAIDRedundant Array of Independent Disks, storage layouts that trade off performance and fault tolerance3.3 Storage Devices, Interfaces & RAID Basics
SMARTStorage health reporting system that surfaces warning signs on drives3.3 Storage Devices, Interfaces & RAID Basics
SOHOSmall office or home office environment2.2 Addressing, TCP/IP & SOHO Foundations
UEFIUnified Extensible Firmware Interface, the modern firmware environment that replaced older BIOS behavior in many systems3.1 Motherboards, Firmware, CPUs & Memory
VDIVirtual desktop infrastructure, where desktops run centrally and are delivered to users remotely4.2 Cloud Models, Thin Clients & VDI Basics
WPSWi-Fi Protected Setup, a convenience feature that is usually a bad security choice in SOHO setups2.3 Wireless Standards, Encryption & SOHO Connectivity

Commonly confused pairs

PairQuick distinction
M.2 vs NVMeM.2 is a form factor; NVMe is a storage protocol
SATA vs NVMeSATA is slower and older; NVMe usually rides over PCIe and is faster
BIOS vs UEFIBIOS is the older firmware model; UEFI is the newer one with richer boot and security features
Snapshot vs backupSnapshot is a short-term state capture; backup is the safer recovery copy
Hotspot vs tetheringHotspot usually shares mobile data as Wi-Fi; tethering can also mean USB or Bluetooth sharing
2.4 GHz vs 5 GHz vs 6 GHz2.4 reaches farther but crowds easily; 5 and 6 GHz usually give better throughput with shorter range
Ghosting vs streakingGhosting often points to fuser or drum behavior; streaking often points to toner, drum, or contamination patterns

Fast recall anchors

  • 169.254.x.x usually means a DHCP path problem
  • names fail but IP works usually points to DNS first
  • RAID 10 means redundancy plus strong performance, but it needs more disks
  • WPA3 is better than WPA2, and WEP is not acceptable today
  • Snapshots are not safe substitutes for true backups

Go back to the cheat sheet for fast review or the study plan if you need a more structured prep order.

Cheat Sheet
FAQ