A Cisco switch has four main internal memory components. These memory components are the Random-Access Memory (RAM), Non-Volatile RAM (NVRAM), Read Only Memory (ROM) and Flash Memory. NVRAM is the memory component that retains stored information even after the device is powered down. Because of this, the startup-config file is stored in the NVRAM. If there is no startup configuration, the switch enters the setup utility and loads a default configuration.
Cisco 交換器有四個主要的內部記憶體元件，分別是隨機存取記憶體（RAM）、非揮發性 RAM（NVRAM）、唯讀記憶體（ROM）與快閃記憶體（Flash Memory）。NVRAM 是即使裝置關機後仍會保留已儲存資訊的記憶體元件，因此啟動設定檔（startup-config）會儲存在 NVRAM 中。若沒有啟動設定，交換器會進入設定精靈並載入預設設定。
The RAM is the memory component that contains the running configuration. When the device starts, the system copies the startup configuration to the RAM. RAM does not retain stored information when the device is rebooted or powered off. Changes made to the running configuration should be copied to the startup-config file in the NVRAM.
RAM 是包含執行中設定（running configuration）的記憶體元件。裝置啟動時，系統會將啟動設定複製到 RAM 中。RAM 在裝置重新開機或關機時不會保留已儲存的資訊。對執行中設定所做的變更，應複製到 NVRAM 中的啟動設定檔。
The ROM memory component is a form of permanent storage in the switch. This memory component contains a microcode for basic functions to start and maintain the device. ROM is nonvolatile, so it maintains stored information even when the device is rebooted or powered off.
ROM 記憶體元件是交換器中的一種永久性儲存裝置，內含用於啟動與維持裝置基本功能的微碼。ROM 是非揮發性的，因此即使裝置重新開機或關機，仍會保留已儲存的資訊。
ROM contains:
ROM 包含：
- The bootstrap code, which is used to bring up the device during initialization.開機碼（bootstrap code），用於在初始化期間啟動裝置。
- Power on self-test (POST) microcode, which is used to test the basic functionality of the switch hardware to determine which components are present.開機自我測試（POST）微碼，用於測試交換器硬體的基本功能，以判斷哪些元件存在。
- ROM monitor includes a low-level operating system that is normally used for manufacturing, testing, troubleshooting and password recovery.ROM 監視器（ROM monitor）包含一個低階作業系統，通常用於製造、測試、疑難排解與密碼復原。
The Flash memory is like a hard drive. Information stored here is maintained even if the device reboots or is powered off. Cisco IOS Software is stored in the flash memory. Backup configuration files may also be stored in the flash memory.
快閃記憶體（Flash memory）類似硬碟。儲存在此的資訊即使在裝置重新開機或關機後仍會保留。Cisco IOS 軟體即儲存於快閃記憶體中，備份設定檔也可能儲存於此。
