1What is computer memory?
In digital electronics, memory is a physical device that stores data/information or instructions temporarily or permanently in digital systems like computers. It is made of semiconductor materials and provides storage space for data and instructions.
2Differentiate between Primary Memory and Secondary Memory.
Primary Memory is volatile, faster, and directly accessible by the CPU (e.g., RAM, ROM). Secondary Memory is non-volatile, slower, and used for long-term storage (e.g., HDDs, SSDs, USB drives).
3What is memory hierarchy in a computer system?
Memory hierarchy is the arrangement of memory types based on speed and capacity. As you go down the hierarchy, storage capacity increases, cost per bit decreases, access frequency decreases, and access time increases.
4What are Registers in the memory hierarchy?
Registers are the fastest and smallest memory units within the CPU, used to temporarily hold data, instructions, and addresses for immediate processing. They are volatile.
5What is Cache Memory and where is it placed?
Cache Memory is a small, fast, volatile memory located between the CPU and RAM, storing frequently accessed data and instructions to speed up processing.
6Name and describe the three levels of cache memory.
L1 is the smallest and fastest cache inside each CPU core. L2 is larger, inside or outside the CPU, and may be shared. L3 is the largest, outside the CPU, and shared across cores.
7Differentiate between SRAM and DRAM.
SRAM is fast, expensive, and retains data with power (no refreshing needed). DRAM is slower, cheaper, and needs constant refreshing via a controller to retain data.
8What is DDR SDRAM and its evolution?
DDR SDRAM is a DRAM synchronized with the system clock that transfers data on both edges of the clock cycle. Newer generations like DDR2–DDR5 offer faster speeds and better efficiency.
9What is ROM and how is it different from RAM?
ROM is non-volatile memory that stores data permanently, such as system boot programs. Unlike RAM, ROM retains data without power and cannot be easily modified.
10Name and briefly describe four types of ROM.
PROM is write-once. EPROM is erased by UV light. EEPROM is electrically erasable but requires removal. Flash ROM is reprogrammable in the device and used in USBs and SSDs.
11What are the main purposes of using secondary memory?
To store data permanently, provide large storage capacity, and allow data portability between systems using removable storage.
12List the four types of computer storage devices.
Magnetic Storage, Optical Storage, Flash Memory, and Cloud/Virtual Storage.
13Give examples of Magnetic Storage Devices.
Floppy Disks, Hard Disk Drives (HDDs), and Magnetic Cards.
14Give examples of Optical Storage Devices.
CDs (CD-R, CD-RW) and DVDs (DVD-R, DVD-RW), used for storing data on plastic discs.
15Give examples of Flash Memory Devices.
Pen Drives (USB), Solid State Drives (SSDs), and Secure Digital (SD) Cards.
16What is Cloud and Virtual Storage?
Storage where data is kept on remote servers owned by service providers and accessed via the internet, offering scalability and flexibility without direct hardware interaction.
17List the common units of memory capacity.
bit, nibble (4 bits), byte (8 bits), kilobyte (1024 bytes), megabyte (1024 KB), gigabyte (1024 MB), terabyte (1024 GB), petabyte (1024 TB)