Configuring Your Router with <copy> and TFTP
Configuration EXEC mode is fine for simple adds and changes. For large changes (such as static routing table or ACL maintenance), the command line is just not practical. In addition to the <write network> command, the IOS also provides <copy>. The command uses a "from-to" syntax style similar to the DOS copy command. The <copy> command is used to copy files on and off the router's NVRAM, DRAM, and flash "file systems" (running or startup configuration, or the IOS). To see the contents of the router's memory file systems, the <show> and <dir> (12.x only) commands are needed.
Cisco, in later versions (12.x) of the IOS, uses the term file system to describe memory (originally with only the 7x00 ...