default -- mark the default-branch within a switch-statement
The default-clause is an optional part of the switch-statement (see there for more information). It introduces a series of statements, that should be executed, if none of the casese matches, that have been specified before (each with its own case-clause). So default specifies a default to be executed, if none of the explicitly named cases matches; hence its name.
print "Please enter a number between 0 and 6,"
print "specifying a day in the week."
case 0:print "Monday":break
case 1:print "Tuesday":break
case 2:print "Wednesday":break
case 3:print "Thursday":break
case 4:print "Friday":break
case 5:print "Saturday":break
case 6:print "Sunday":break
default:print "Hey you entered something invalid!"
This program translates a number between 0 and 6 into the name of a weekday; the default -case is used to detect (and complain about) invalid input.