A solid state drive stores data using
- A.Magnetic platters that rotate
- B.Flash memory chips
- C.Pits read by a laser
- D.Magnetic tape wound on reels
Correct answer
Explanation
The correct answer is B, flash memory chips. An SSD is built from flash memory, itself a block-erasable form of EEPROM, which traps charge in floating-gate cells. Because there is no motor, no platter and no head, an SSD has no seek time, makes no noise and stands up to being knocked about, which is why it has replaced the hard disk in most new machines.
Option A describes the hard disk drive, where data is written magnetically on spinning platters along tracks, sectors and cylinders. Option C describes optical media, the CD, DVD and Blu-ray disc, where a laser burns and reads pits and lands on a reflective layer. Option D describes magnetic tape, the archival medium and the standard example of sequential access storage. All four are secondary storage: the SSD differs in technology, not in its place in the memory hierarchy.
Read the full article: Memory and Storage: RAM, ROM, Cache and Units
Practice Questions
View allWhich of the following is the fastest memory in a computer system?
- A.Cache memory
- B.Register
- C.Main memory
- D.Hard disk
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A register is built into the CPU itself and holds the word the arithmetic and logic unit is operating on at that instant, so it is read and written in a single clock cycle.
Read the full explanation →How many bits make one nibble?
- A.2 bits
- B.4 bits
- C.8 bits
- D.16 bits
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A nibble is half a byte, that is four binary digits, and it matters because one nibble is written as exactly one hexadecimal digit, from 0 to F. That is why memory addresses in hexadecimal are read four bits at a time.
Read the full explanation →Which type of memory has to be refreshed thousands of times per second to retain its contents?
- A.SRAM
- B.DRAM
- C.ROM
- D.Flash memory
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Dynamic RAM stores each bit as a charge on a very small capacitor, and that charge leaks away in a few milliseconds, so the memory controller has to read and rewrite every cell continuously.
Read the full explanation →The contents of an EPROM chip are erased by exposing it to
- A.An electrical signal
- B.Ultraviolet light
- C.A magnetic field
- D.Infrared radiation
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An Erasable Programmable Read Only Memory chip carries a small quartz window over the silicon; ultraviolet light shone through that window releases the trapped charge from every cell at once and returns the chip to its blank state, after which it can be programmed again.
Read the full explanation →One terabyte is equal to how many gigabytes?
- A.100 GB
- B.512 GB
- C.1,024 GB
- D.2,048 GB
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Every step in the ladder of storage units multiplies by 1,024, because 1,024 is 2 raised to the power 10 and memory is addressed in binary.
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