Comptia A+ 220-1201 Core 1

Laptop RAM

Commonly installed as SODIMM memory modules in laptops.

SODIMM

Small Outline Dual Inline Memory Module; laptop-sized RAM.

DIMM

Desktop-sized memory module.

Laptop storage upgrade

Commonly uses 2.5-inch SATA SSDs or M.2 NVMe SSDs depending on system design.

M.2

A small-form-factor connector used for SSDs and some Wi-Fi/Bluetooth cards.

NVMe

A storage protocol used over PCIe for fast SSD performance.

2.5-inch SATA SSD

A solid-state drive using SATA interface, common in laptops and desktops.

HDD

Hard disk drive; larger capacity and lower cost per gigabyte than SSD, but slower.

SSD

Solid-state drive; faster than HDD and has no moving parts.

Laptop battery types

Modern laptops commonly use lithium-ion or lithium-polymer batteries.

Laptop webcam

Used for video conferencing and remote meetings.

Microphone mute switch

A laptop feature that disables audio input for privacy/security.

Function key

Used with Fn to access brightness, volume, wireless, and other laptop features.

Docking station

Expands laptop connectivity with extra ports, displays, and peripherals.

Port replicator

Provides additional ports but usually with less functionality than a full docking station.

Biometrics on mobile devices

Commonly fingerprint readers or facial recognition.

NFC

Near Field Communication; short-range wireless used for tap-to-pay and quick pairing.

Bluetooth

Short-range wireless used for headsets, keyboards, mice, and file transfer.

Tethering

Sharing a phone's internet connection with another device.

Mobile hotspot

A smartphone feature that provides Wi-Fi internet access to other devices.

PRL update

Preferred Roaming List update; helps a mobile device connect to carrier networks.

MFA on mobile devices

Multi-factor authentication using something you know, have, or are.

Screen rotation

Controlled by accelerometer/gyroscope sensors in mobile devices.

GPS

Global Positioning System used for location and navigation.

OLED display

Screen technology with strong contrast and deep blacks.

LCD display

Liquid crystal display; common flat-panel display type.

Digitizer

Converts touch or stylus input into digital signals.

Stylus

A pen-like input device for touchscreens or digitizers.

Biometric lockout

Troubleshooting may involve re-enrollment or fallback PIN/password methods.

No cellular connectivity on phone

Check airplane mode, SIM/eSIM status, carrier settings, and signal strength.

Poor battery life on mobile device

Check screen brightness, background apps, battery health, and radios in use.

Dim display on mobile device

Check brightness settings, adaptive brightness, and battery saver mode.

Ghost touches

Possible digitizer issue causing unintended screen input.

Bluetooth pairing issue

Delete pairing, re-pair, ensure discoverable mode, and verify distance/power.

Wi-Fi drops on tablet

Check signal strength, SSID, channel congestion, and saved wireless profile.

Laptop not charging

Check AC adapter, USB-C/charging port, battery health, and DC jack.

TCP

Transmission Control Protocol; connection-oriented and reliable.

UDP

User Datagram Protocol; connectionless and lower overhead.

Port number

Logical identifier for network services.

HTTP

Port 80; unencrypted web traffic.

HTTPS

Port 443; encrypted web traffic using TLS.

SSH

Port 22; secure remote terminal access.

Telnet

Port 23; insecure remote terminal access.

FTP

Ports 20/21; file transfer protocol.

SFTP

Secure File Transfer Protocol, typically over SSH on port 22.

RDP

Port 3389; Remote Desktop Protocol.

SMB

Server Message Block; file/printer sharing, often on port 445.

DNS

Resolves hostnames to IP addresses.

DHCP

Automatically assigns IP configuration to clients.

APIPA

Automatic Private IP Addressing; 169.254.x.x self-assigned address when DHCP fails.

IPv4

32-bit addressing format such as 192.168.1.10.

IPv6

128-bit addressing format designed to replace IPv4.

Subnet mask

Identifies which portion of an IP address is the network vs host.

Default gateway

Router IP used to reach devices outside the local subnet.

Static IP

Manually assigned IP address.

Dynamic IP

Automatically assigned, usually via DHCP.

Private IPv4 ranges

10.0.0.0/8, 172.16.0.0-172.31.255.255, and 192.168.0.0/16.

DNS record A

Maps a hostname to an IPv4 address.

DNS record AAAA

Maps a hostname to an IPv6 address.

DNS record CNAME

Alias that points one hostname to another.

DNS record MX

Identifies mail servers for a domain.

DNS record TXT

Text record often used for verification and email security policies.

SPF

Sender Policy Framework; helps validate sending mail servers.

DKIM

DomainKeys Identified Mail; email signing for authenticity.

DMARC

Policy framework using SPF and DKIM results to handle suspicious email.

VPN

Virtual Private Network; creates encrypted remote access over untrusted networks.

SOHO

Small office/home office network environment.

Router

Directs traffic between networks.

Switch

Connects devices within the same local network using MAC addresses.

Access point

Provides wireless network connectivity.

Modem

Converts ISP service signal for internet connectivity.

NIC

Network Interface Card; connects a device to a network.

MAC address

Hardware address assigned to a network interface.

SSID

Name of a wireless network.

WPA2

Common wireless security standard using AES.

WPA3

Newer wireless security standard with stronger protections.

2.4 GHz Wi-Fi

Longer range, lower speed, more interference.

5 GHz Wi-Fi

Higher speed, shorter range, less interference than 2.4 GHz.

6 GHz Wi-Fi

Used by Wi-Fi 6E/7 for higher capacity and lower congestion where supported.

Omnidirectional antenna

Broadcasts signal in multiple directions.

Directional antenna

Focuses wireless signal in one direction.

Patch panel

Cable termination point used in structured cabling.

Punchdown tool

Used to seat wires into patch panels or keystone jacks.

Crimper

Used to terminate network cable ends, such as RJ45 connectors.

Cable tester

Verifies wiring continuity and pinout.

Loopback plug

Used to test NICs and network ports.

Toner probe

Helps trace and identify cables.

Wi-Fi analyzer

Used to inspect SSIDs, channels, and signal strength.

PoE

Power over Ethernet; sends data and electrical power on the same cable.

RJ45

Common connector for Ethernet twisted-pair cabling.

Cat 5e

Supports gigabit Ethernet in many scenarios.

Cat 6

Improved cabling standard supporting higher performance than Cat 5e.

Fiber optic cable

Uses light, supports long distance and high bandwidth.

ST fiber connector

A bayonet-style fiber connector.

SC fiber connector

A square push-pull fiber connector.

LC fiber connector

A small-form-factor fiber connector.

WAN

Wide Area Network connecting sites over large geographic distances.

LAN

Local Area Network within a limited area.

VPN concentrator

Device that manages multiple VPN connections.

Intermittent wireless connectivity

Check interference, signal strength, channel overlap, and driver issues.