RAM和ROM之间的区别

先决条件–计算机内存类型(RAM和ROM)
随机存取存储器(RAM)用于实时存储CPU正在使用的程序和数据。随机存取存储器上的数据可以被读取，写入和擦除任意次。 RAM是存储当前使用的数据的硬件元素。它是易失性存储器。 RAM类型：

1. 静态RAM或(SRAM)，它使用六个晶体管存储单元的状态存储一点数据。
2. 动态RAM或(DRAM)，它使用构成DRAM存储单元的一对晶体管和电容器来存储位数据。

只读存储器(ROM)是一种已预先记录数据的存储器。即使在计算机关闭后(即非易失性)，仍会保留ROM中存储的数据。 ROM的类型：

1. 可编程ROM ，在创建存储芯片后将数据写入其中。它是非易失性的。
2. 可擦可编程ROM ，该非易失性存储芯片上的数据可以通过将其暴露于高强度紫外线下而擦除。
3. 电可擦可编程ROM ，该非易失性存储芯片上的数据可以使用场电子发射进行电擦除。
4. 掩模ROM ，在存储芯片的制造过程中将数据写入其中。

下表区分了ROM和RAM：

Difference	RAM	ROM
Data retention	RAM is a volatile memory which could store the data as long as the power is supplied.	ROM is a non-volatile memory which could retain the data even when power is turned off.
Working type	Data stored in RAM can be retrieved and altered.	Data stored in ROM can only be read.
Use	Used to store the data that has to be currently processed by CPU temporarily.	It stores the instructions required during bootstrap of the computer.
Speed	It is a high-speed memory.	It is much slower than the RAM.
CPU Interaction	The CPU can access the data stored on it.	The CPU can not access the data stored on it unless the data is stored in RAM.
Size and Capacity	Large size with higher capacity.	Small size with less capacity.
Used as/in	CPU Cache, Primary memory.	Firmware, Micro-controllers
Accessibility	The data stored is easily accessible	The data stored is not as easily accessible as in RAM
Cost	Costlier	cheaper than RAM.