Cisco devices typically have four types of memory that are used for different purposes. These four types are:
*ROM (read-only memory) - stores a bootstrap program used to initiate a boot process. This is a read only memory that cannot be changed.
*Random Access Memory - Stores the current configuration and routing tables on the device. This type of memory loses content when a device is restarted.
*Flash Memory - Used to store IOS software images. Can also be used to save other files, eg. B. Back up configuration files. Maintains content even after a device has restarted.
*NVRAM (nonvolatile RAM) - is usually used to store a boot configuration file. With this type of memory, the content is retained even when a device is turned off or restarted.