Data Storage Systems - Memory and Storage Basics

Vocabulary flashcards covering key concepts, terms, and memory/storage components from the lecture notes on data storage systems and memory management.

RAM (Random Access Memory)

Volatile primary memory that stores data and instructions temporarily for the CPU to access; contents are lost when power is turned off.

ROM (Read-Only Memory)

Non-volatile permanent storage memory that is typically read-only and holds essential instructions used repeatedly.

DRAM (Dynamic RAM)

A type of RAM that stores data in capacitors and requires constant refreshing to retain information.

SRAM (Static RAM)

A faster RAM type that does not require refreshing, commonly used for cache and quick data access.

DDR RAM (Double Data Rate RAM)

An enhanced DRAM that transfers data twice per clock cycle; newer versions include DDR4 and DDR5.

PROM (Programmable ROM)

ROM that can be programmed once during manufacturing before use.

EPROM (Erasable Programmable ROM)

ROM that can be erased (often with UV light) and reprogrammed.

EEPROM (Electrically Erasable Programmable ROM)

ROM that can be erased and rewritten using electrical signals.

HDD (Hard Disk Drive)

Non-volatile secondary storage with spinning platters for long-term data retention.

SSD (Solid State Drive)

Secondary storage using flash memory with no moving parts; faster and more durable than HDD.

USB Drive

Portable external storage device that connects via USB for easy data transfer.

Memory Card

Portable external storage used in devices like cameras and smartphones.

Optical Disc

Storage media (CDs/DVDs/Blu-ray) that uses laser technology to read/write data; usage declining with USB drives.

Cache Memory

Small, high-speed volatile memory between CPU and RAM that stores frequently accessed data to speed up processing.

Registers

Small, fast storage locations inside the CPU for temporary data, results, and addresses during instruction execution.

GPU (Graphics Processing Unit)

Specialized processor with many cores that handles graphics and video processing, offloading work from the CPU.

CPU (Central Processing Unit)

The main processor of a computer that executes instructions and coordinates activities.

ALU (Arithmetic Logic Unit)

A sub-unit of the CPU that performs arithmetic and logical operations.

Primary Memory

Memory directly accessible by the CPU (main memory), typically RAM.

Secondary Memory

Permanent storage outside RAM (HDDs, SSDs, etc.) used for long-term data storage.

Bit

Binary digit; the smallest unit of digital data, either 0 or 1.

Byte

8 bits; a basic unit of storage.

Kilobyte (KB)

1024 bytes.

Megabyte (MB)

1024 kilobytes.

Gigabyte (GB)

1024 megabytes.

Terabyte (TB)

1024 gigabytes.

Petabyte (PB)

1024 terabytes.

Exabyte (EB)

1024 petabytes.

Zettabyte (ZB)

1024 exabytes.

Yottabyte (YB)

1024 zettabytes.

Memory Allocation

OS assigns RAM to programs as needed; involves loading, execution, and dynamic allocation.

Dynamic Memory Allocation

The process by which the OS allocates additional RAM to a program during runtime as required.

Memory Deallocation

OS frees previously allocated memory when a program finishes to be used by others.

Loading

Copying necessary data and instructions from storage into RAM for execution.

Execution

CPU processes and carries out instructions using data stored in memory.

Non-volatile Memory

Memory that retains data without power, such as ROM, HDD, and SSD.

Volatile Memory

Memory that loses its contents when power is removed, such as RAM and cache.

Task Manager

A Windows utility that monitors running processes, RAM/CPU usage, and performance.