what are read/write operations involved in main memory, cache and processor? please bear with me, I always get confused with the terminologies used in my computer architecture class.

What are read and write operations exactly? What are their relationship with processor, main memory, and cache?

I always thought that load/store are interchangeable with read/write... 

What about the modify operation?
Read is the same as load, and write is the same as store. Modify is a combination of both.