Internal Memory

ROM (Read-Only Memory)
Non-volatile memory used to store data that should remain even when power is removed, such as firmware. Traditionally read-only, although modern ROM technologies can be programmable.

RAM (Random Access Memory)
Volatile memory used for temporary storage of data and instructions while the computer is running. It mainly consists of SRAM and DRAM.

SRAM

SRAM (Static RAM)
Volatile memory that stores each bit using a bistable circuit, typically a 6-transistor cell. It is fast and does not require refresh, but it is larger and more expensive per bit than DRAM. Commonly used for CPU caches.

FF / Latch
Basic storage elements used to store digital state. A flip-flop stores one bit and is edge-triggered, while a latch is level-sensitive. SRAM cells are based on similar bistable storage principles, although a standard SRAM cell is not simply a flip-flop.

SRAM Cell
The basic building block of SRAM that stores one bit. A typical 6T SRAM cell consists of two cross-coupled inverters and two access transistors.

Small Signal
Small-signal analysis is used to analyze the behavior of transistor circuits around a particular operating point. In SRAM design, it can be used to study parameters such as stability, gain, and noise margins.

DRAM

DRAM (Dynamic RAM)
Volatile memory that typically stores each bit using a capacitor and transistor (1T1C). The capacitor leaks charge, so the memory requires periodic refresh. DRAM is slower than SRAM but much denser and cheaper per bit, making it suitable for main memory.

External Memory / Storage

HDD (Hard Disk Drive)
Non-volatile magnetic storage that uses rotating disks and mechanical read/write heads. It offers high capacity at relatively low cost but is slower than SSDs.

SSD (Solid-State Drive)
Non-volatile storage based on NAND Flash memory. It has no moving mechanical parts and provides much faster access than HDDs.

CD (Compact Disc)
Optical, non-volatile storage. Data is stored and read using a laser. CDs have relatively low capacity and are less common in modern computers.

USB
A USB flash drive is portable, non-volatile storage, typically based on NAND Flash. It is used for transferring and storing data

Overview