The Big Picture: Your Word List
A glossary is a mini dictionary. Come back here whenever a word feels fuzzy. The "Example" column shows the term in real life.
Fundamental Terms
| Term | Meaning | Example |
|---|
| Hardware | Physical electronic components you can touch | CPU, RAM, motherboard, GPU |
| Software | Programs and code | Windows, Chrome, your documents |
| Firmware | Code stored on a chip, runs before OS | BIOS, UEFI, GPU firmware |
| Driver | Software that controls hardware | GPU driver, printer driver, NIC driver |
| Bus | Pathway for data between components | PCIe, USB, system bus |
| Controller | Processor managing a device | USB controller, storage controller |
| Kernel | Core of operating system | Windows NT kernel |
| User mode | Restricted execution level | Your applications run here |
| Kernel mode | Unrestricted execution level | Windows kernel runs here |
| Interrupt | Signal to pause and handle event | Disk read complete, network packet arrived |
| DMA | Direct Memory Access — hardware reads/writes RAM without CPU | Disk controller writes to RAM |
| Term | Meaning |
|---|
| Core | Independent processor on a CPU |
| Thread | Independent execution stream (one line of work) |
| Register | Ultra-fast memory inside CPU |
| Cache | Fast memory near CPU (L1, L2, L3) |
| Instruction | Single operation CPU performs |
| Clock | Timing signal that synchronizes CPU |
| Frequency/GHz | How many billion instructions per second |
| Term | Meaning |
|---|
| RAM | Fast temporary memory |
| Virtual memory | Technique extending RAM using storage |
| Paging | Moving memory blocks between RAM and storage |
| Address | Location of data in memory (like a house number) |
| MMU | Memory Management Unit — translates addresses |
| TLB | Translation Lookaside Buffer — address cache |
| Term | Meaning |
|---|
| HDD | Hard Disk Drive — magnetic storage |
| SSD | Solid State Drive — electronic storage |
| SATA | Connection type for storage |
| NVMe | Faster connection type for storage |
| Platter | Rotating disk in HDD |
| NAND | Type of flash memory in SSDs |
Summary
| Group | What it covers |
|---|
| Fundamental | Hardware, software, firmware, drivers, buses, kernel, interrupts, DMA |
| CPU | Core, thread, register, cache, instruction, clock, GHz |
| Memory | RAM, virtual memory, paging, address, MMU, TLB |
| Storage | HDD, SSD, SATA, NVMe, platter, NAND |