history of the computers

 history of the computers 

early computers used relays mechanical counters or delay lines for main memory 

functions ultrasonic delay lines were serial devices which could only reproduce 

data in the order it was written  drum memory.could be expanded at rekatively

low cost but effcient retrieval of out of discrete transistors were used for smaller

and faster.memories such registers such registers were relatively large and

too costly to use for large amout of data generally only a few hundred bits of such could be provided

random access memory

 random access memory is a form of computer memory that can be read and 

change that can be read and change in the any order typically used to store 

working data and machine code.ram contains the multiplexing and demulplexing circurity to 

circuitry to connect the data lines to the addressed storage for reading or writing the entry usuawlly

more than one bit of the storage is accessed by the same address and ram device often have multiple data 

lines and are said to be 8 bit or 16 bit etc.devices

in today techonology ramdom-access memory takesthe form of intergrated circuit chips mos memory cells

ram is normally associated with the volatile types of memory such as dynamic random access memory dram module 

the two main types of the volatile memory random access semiconductor memory are the static random access memory and 

dyanamic random access memory commercial users of semiconductor ram data back to 1965

when ibm introduce the sp95

chip for their system 360 module modle 95 computer and toshiba used dram memory cells for its toscal