What is a Ram? What is a ROM? What is a HDD?

What is a RAM? What is a ROM? 

Ram or 'Random Access Memory' is a 'computer memory'(Internal storage
areas in a computer) that can be accessed randomly. Here randomly signifies
that any number of 'bytes' of memory can be approached(read/write) 
without touching and disturbing the other preceding 'bytes'. Bytes( abbreviation
of Binary) signifies a 'unit' of storage. One byte is capable of holding a 
single character. In latest computers one 'byte' is equal to 8 'bits'. Memories
are indicated in terms of 'kilobytes'(KB), 'megabytes'(MB) or 'gigabytes(GB).
For instance, a specific file may contain (2,025 bytes) or it may contain
(5.215.743 bytes) or (3,985,486.000 bytes) and so on.

Ram may be of two types - Dynamic Random Access Memory(DRAM) or
Static Random Access Memory(SRAM). These two types of  RAM differ
in technology and their application. DRAM is the most common type of 
RAM used in our computers nowadays though SRAM is faster. Common 
users of computers, for whose knowledge this blog is intended, need not go 
into further complex  technology of RAM. They are meant for technical personnel.

Rom or 'Read Only Memory' is a type of storage medium used in computers
and other electronic appliances. Data stored in ROM can be read but cannot
be easily modified/changed. It is mainly used in 'software'(programs) that is 
closely linked to efficient functioning of some 'Hardware'(hard disc drive HDD, 
mouse, monitor, keyboard, printer, motherboard and many more). Again 
general users of computers need not overload their brains to know every 
structure and program of  ROM as they are meant for 'Software & Hardware 
Engineers'

How to Replace RAM....Watch

What is a Hard Disc Drive or HDD?

The hard disc drive or HDD is the biggest data storage hardware/device 

inside a personal computer. A hardware means all the physical components 

of a computer that make up a full computer system e.g. HDD/SMPS/Mouse

/Keyboard/Monitor/RAM/CPU/Motherboard and many more). The HDD is

sometimes referred to as 'Hard Drive' also. The basic function of HDD is to

store and also retrieve data as when required. The size of a HDD may be 3.5"

or 2.5" for a PC or Laptop respectively. 

A Hard Drive may comprise one or more Platters (small disk of aluminium/

glass or ceramic coated in a magnetic media on which the computer writes the

data. As soon as the computer starts, the platter starts to rotate and the read/

write head touching the platter starts retrieving the data or writes fresh data

on it.just like a Tape Recorder or CD ROM player/writer. The data in the Platter

is stored in various tracks, sectors and cylinders to enable the user to locate

specific data efficiently and quickly. When listening to songs/music on a CD, we

find different songs on different track for easy access.  

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