A Comprehensive Guide to Home Security Systems:

 

WHAT IS RAM?

RAM: Ram stand for (Random access memory).Ram is a internal memory of CPU for storing data,program and results of program is the hardware in a computer device. our data is save in the ram.Ram is the main memory in a computer.A computer also works this way.If ram fills up,the computer,s processor must repeatedly go to the hard disk to overly the old data is ram with new data.this process slows the computer operation.Ram is essentially a device,s short-term memory.

TYPE OF RAM:

DRAM,SRAM

DRAM:

DRAM stands for dynamic random access memory.Dram recharged or refreshed again and again to maintain its content or data.Processor cannot access the data or content of DRAM when it is being refreshed that,s why it is slow.Its is Least expensive kind of ram.

SRAM: 

SRAM stands for static random access memory.The word static mean that it does not need to frequent recharging as DRAM.Memory retains it,s content as long as power is being supplied due to its volatile nature cup does not need to wait to access data from SRAM during processing.That,s why faster than DRAM.

WHAT IS ROM?

ROM:

ROM stands for ( READ ONLY MEMORY ).The instructions in rom prepare the computer for use.These instructions can only be read but can not be changed or deleted.Rom stores data and instructions permanently.When the power is switched off,the instructions stored in rom are not lost.That is why Rom is known as non-volatile memory.Rom data is permanent data can,t be modified data to be copied from ROM to RAM so, that CPU can access its data ROM is slower than RAM.

TYPE OF ROM:

 PROM, EPROM,EEPROM

PROM:  

PROM stands for programmable read only memory.This form of Rom initially blank.The user or manufacturer can write data and programs on its using special devices.The user can write data and instructions on it only once .

EPROM: 

 EPROM stands for erasable programmable read on;y memory.This foam of Rom intially blank the user or manufacture can be write data and programs on it using special devices.The data and program written on it can be erased with special devices using ultraviolet rays.

EEPROM:

 EEPROM stands for electronically erasable programmable read only memory.In this memory, user can erase and write instructions with the help of electrical pulses.The content of EEPROM can be modified easily.

WHAT IS PRIMARY MEMORY?

PRIMARY MEMORY:

 Primary memory is a section of computer memory that the cup can access directly.Primary memory has a faster access time than secondary memory and is faster than cache memory in a memory hierarchy.

WHAT IS SECONDARY MEMORY?.

SECONDARY MEMORY: 

SECONDARY memory is the memory where program and data stored permanently.Secondary memory is an external memory Secondary memory Is a non-volatile memory this means data and program stored in it are not lost.