以下说法待验证：
Precharge is the first operation in the initialization phase…
If we want to open a new Row then we need to close the previous row to operate functionally well, because of this we do precharge operation.
As in dynamic ram charge is stored onto a capacitor and since capacitor can store charge indefinitely we need to refresh them.
2 types of Refresh operation
1)Auto Refresh done by controllor
2)Self Refresh automatically done by Memory