CompTIA A+ Core 1 (220-1201)
Beginner-Friendly Study Guide & Quick Reference
LearnStack
A concise original study guide covering the major technical areas commonly associated with CompTIA A+
Core 1. Use it as a revision aid alongside current official exam objectives and hands-on practice.
Important: This is an independent study resource and is not affiliated with or endorsed by CompTIA. It does
not contain official CompTIA exam questions.
, 1. Mobile Devices
• Mobile devices combine compact hardware, wireless connectivity, operating systems, sensors, and
power management.
• Key areas: smartphones and tablets, touchscreens, cameras, microphones, GPS, NFC, Bluetooth, Wi-Fi,
cellular connectivity, biometrics, and device synchronization.
• Common connections: USB-C is widely used for charging and data. Bluetooth is commonly used for
short-range peripherals. NFC is designed for very short-range communication such as tap-to-pay.
• Troubleshooting approach: confirm power, check connectivity, restart the device, verify settings and
updates, test with a known-good accessory, and isolate whether the problem follows the device or
accessory.
2. Networking
• Understand the purpose of common networking devices and technologies. A router connects different
networks and commonly performs routing and NAT. A switch connects devices within a LAN. An access
point provides wireless network access.
• Common concepts: IPv4, IPv6, DHCP, DNS, TCP/IP, Ethernet, Wi-Fi, VPN, NAT, and subnetting
fundamentals.
• Useful ports to remember: HTTP 80, HTTPS 443, DNS 53, DHCP 67/68, SSH 22, FTP 20/21, RDP
3389, and SMTP 25.
• Wi-Fi troubleshooting: check signal strength, SSID selection, authentication, interference, IP
configuration, DHCP availability, and whether other devices can connect.
3. Hardware
• CPU: executes instructions and performs calculations. Important characteristics include cores, clock
speed, cache, and architecture.
• RAM: temporary working memory. Insufficient RAM can contribute to slow multitasking and increased
paging.
• Storage: HDDs use magnetic platters; SSDs use flash memory and generally provide faster access and
better resistance to physical shock.
• Motherboard: provides connections for the CPU, RAM, expansion devices, storage, and other
components.
• Power supply: converts AC input to regulated DC power for computer components. A failing PSU can
produce instability, shutdowns, or failure to boot.
4. Virtualization & Cloud Concepts
• Virtualization allows multiple virtual systems to run on shared physical hardware through a hypervisor.
Beginner-Friendly Study Guide & Quick Reference
LearnStack
A concise original study guide covering the major technical areas commonly associated with CompTIA A+
Core 1. Use it as a revision aid alongside current official exam objectives and hands-on practice.
Important: This is an independent study resource and is not affiliated with or endorsed by CompTIA. It does
not contain official CompTIA exam questions.
, 1. Mobile Devices
• Mobile devices combine compact hardware, wireless connectivity, operating systems, sensors, and
power management.
• Key areas: smartphones and tablets, touchscreens, cameras, microphones, GPS, NFC, Bluetooth, Wi-Fi,
cellular connectivity, biometrics, and device synchronization.
• Common connections: USB-C is widely used for charging and data. Bluetooth is commonly used for
short-range peripherals. NFC is designed for very short-range communication such as tap-to-pay.
• Troubleshooting approach: confirm power, check connectivity, restart the device, verify settings and
updates, test with a known-good accessory, and isolate whether the problem follows the device or
accessory.
2. Networking
• Understand the purpose of common networking devices and technologies. A router connects different
networks and commonly performs routing and NAT. A switch connects devices within a LAN. An access
point provides wireless network access.
• Common concepts: IPv4, IPv6, DHCP, DNS, TCP/IP, Ethernet, Wi-Fi, VPN, NAT, and subnetting
fundamentals.
• Useful ports to remember: HTTP 80, HTTPS 443, DNS 53, DHCP 67/68, SSH 22, FTP 20/21, RDP
3389, and SMTP 25.
• Wi-Fi troubleshooting: check signal strength, SSID selection, authentication, interference, IP
configuration, DHCP availability, and whether other devices can connect.
3. Hardware
• CPU: executes instructions and performs calculations. Important characteristics include cores, clock
speed, cache, and architecture.
• RAM: temporary working memory. Insufficient RAM can contribute to slow multitasking and increased
paging.
• Storage: HDDs use magnetic platters; SSDs use flash memory and generally provide faster access and
better resistance to physical shock.
• Motherboard: provides connections for the CPU, RAM, expansion devices, storage, and other
components.
• Power supply: converts AC input to regulated DC power for computer components. A failing PSU can
produce instability, shutdowns, or failure to boot.
4. Virtualization & Cloud Concepts
• Virtualization allows multiple virtual systems to run on shared physical hardware through a hypervisor.
