What is the classical difference between main memory and secondary memory?

Project description
Memory is a set of physical storage locations that are addressed via software (programs). It is measured in kilobytes (K), megabytes (MB), gigabytes (GB), or terabytes (TB).

Remember that user memory is temporary. Memory has far less capacity than secondary storage media as in hard disks, zip drives, and CD-R. Memory has in general two parts: RAM (random access memory) and ROM (read-only memory).

Discuss the following questions and topics related to memory:

What is the classical difference between main memory and secondary memory?
Discuss with your classmates the difference between a RAM, ROM, EEPROM (electronically erasable programmable read-only memory), and DRAM (dynamic random access memory)?
What is the difference between internal cache and external cache memory?
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Added on 23.05.2016 15:23
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