cisco IOS Basic Config

line console 0 : global configuration that changes the context to console configuration mode.
line vty 1st-vty 2nd-vty : global config that changes the context to vty configuration mode for the range of vty lines listed in the command.
login : linke (console and vty) configuration mode. Tells IOS to prompt for a password (no usrname).
password pass-value : line (console and vty) config mode. Lists the password required if the login command(with no other params) is configured.
interface type port-number : global command that changes the context to interface mode - ex. interface Fastethernet 0/1.
shutdown/ no shutdown :Interface commands that enables/disables the interface.
hostname name : global command that sets this switches hostname which is also used as the first part of the switch;s command prompt.
enable secret pass-value : global command that sets the automatically encrypted enable secret password. The password is used for any user to reach enable mode.
enable password pass-value : global command that sets the clear text enable password, which is used only when the enable secret password is not configured.
exit : moves back to the next higher mode in configuration mode.
end : exits configuration mode and goes back to enable mode from any of the configuration submodes.
ctrl+z  : this is not a command, but rather a two-key combination that together do the same thing as the end command.
no debug all/ undebug all : enable mode EXEC command to disable all currently enabled debugs.
sow process : EXEC command that lists statistics about CPU utilization
terminal monitor : EXEC command that tells Cisco IOS to send a copy of all syslog messages, including debug messages, to the Telnet or SSH user who issues this command.
reload : enable mode EXEC command that reboots the switch or router.
copy from-location to-location : Enable mode EXEC command that copies files from one file location to another. Locations include the startup-config and running-config files, files on TFTP and RPC servers and flash memory.
copy running-config startup-config : Enable mode EXEC command that saves the active config, replacing the startup-config file used when the switch initialisex.
copy startup-config running-config : Enable mode EXEC command that merges the startup config file with the currently active config file in RAM.
show running-config : Lists the contents of the running-config file.
write erase/erase startup-config/erase nvram:   : All three enable mode EXEC commands erase the startup config file.
setup : Enable mode EXEC command that places the user in setup mode, in which Cisco IOS asks the user for input on simple switch configuration.
quit : EXEC command that disconnects the user from the CLI session
show system: running-config : same as show running-config command
show startup-config : lists the contents of the startup-config file.
show nvram:startup-config/ show nvram:   : same as show startup-config command.
enable : moves the user from user mode to enable(privileged)mode and prompts for an enable password if configured.
disable: moves the user from enable mode to user mode
configure terminal : enable mode command that moves the user into configuration command.